path: root/PbSe_global_analysis/mybib.bib

@article{Besemann2004,
  author =       {Besemann, Daniel M. and Meyer, Kent A. and Wright, John C.},
  title =        {{Spectroscopic Characteristics of Triply Vibrationally
                  Enhanced Four-Wave Mixing Spectroscopy †}},
  journal =      {The Journal of Physical Chemistry B},
  volume =       108,
  number =       29,
  pages =        {10493--10504},
  year =         2004,
  doi =          {10.1021/jp049597l},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp049597l},
  abstract =     {Triply vibrationally enhanced (TRIVE) four-wave mixing is a
                  fully resonant, frequency domain spectroscopy that is capable
                  of coherent multidimensional vibrational spectroscopy. TRIVE
                  has 12 different coherence pathways that differ in their time
                  ordering and resonances. The pathways are the coherent
                  analogue to two-color pump-probe pathways. Specific pathways
                  or sets of pathways can be chosen by appropriate selection of
                  time delays and resonance conditions. The pathways have
                  characteristic positions and line shapes in three-dimensional
                  frequency space and their coherent interference has
                  consequences in interpreting the spectra. The line shapes and
                  the relative intensities of different pathways are dependent
                  on the population relaxation and dephasing rates. The
                  different pathways also have different capabilities for
                  line-narrowing inhomogeneously broadened transitions. The
                  narrowing is controlled by the interference between pathways
                  and the quantum level interference between different parts of
                  the inhomogeneously broadened envelope. We also show that
                  selection of the output frequency in two-color TRIVE methods
                  constrains the selection rules that control the relative
                  transition probabilities of the four transitions.},
  file =         {::},
  issn =         {1520-6106},
  month =        {jul},
}

@article{Block2012,
  author =       {Block, Stephen B. and Yurs, Lena a. and Pakoulev, Andrei V.
                  and Selinsky, Rachel Sarah and Jin, Song and Wright, John C.},
  title =        {{Multiresonant Multidimensional Spectroscopy of
                  Surface-Trapped Excitons in PbSe Quantum Dots}},
  journal =      {The Journal of Physical Chemistry Letters},
  volume =       3,
  number =       18,
  pages =        {2707--2712},
  year =         2012,
  doi =          {10.1021/jz300599b},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jz300599b},
  file =         {::},
  issn =         {1948-7185},
  month =        {sep},
}

@article{BritoCruz1988,
  author =       {{Brito Cruz}, C.H. and Gordon, J.P. and Becker, P.C. and Fork,
                  R.L. and Shank, C.V.},
  title =        {{Dynamics of spectral hole burning}},
  journal =      {IEEE Journal of Quantum Electronics},
  volume =       24,
  number =       2,
  pages =        {261--269},
  year =         1988,
  doi =          {10.1109/3.122},
  url =          {http://ieeexplore.ieee.org/document/122/},
  file =         {::},
  issn =         {0018-9197},
  month =        {feb},
}

@article{Carlson1989,
  author =       {Carlson, Roger J. and Wright, John C.},
  title =        {{Absorption and Coherent Interference Effects in Multiply
                  Resonant Four-Wave Mixing Spectroscopy}},
  journal =      {Applied Spectroscopy},
  volume =       43,
  number =       7,
  pages =        {1195--1208},
  year =         1989,
  doi =          {10.1366/0003702894203408},
  url =
                  {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0003-7028{\&}volume=43{\&}issue=7{\&}spage=1195},
  abstract =     {The effects of coherent interference between resonant and
                  nonresonant signals and the effects of absorption on
                  multiresonant four-wave mixing spectra are investigated both
                  theoretically and experimentally in azu- iene-doped
                  naphthalene crystals at 2 K. Both effects can strongly alter
                  line shapes and intensities. Line splittings and negative
                  spectral features are demonstrated. Coherent interference,
                  although measurable in this system, is weak. Absorption,
                  however, plays an important role, and its effects on phase
                  matching, peak shapes, and peak intensities are pre- dicted
                  theoretically and are confirmed by the experimental measure-
                  ments. A new expression for the four-wave mixing is derived in
                  terms of sample absorption coefficients and absorption cross
                  sections, and gen- eral conditions for maximum efficiency are
                  determined.},
  file =         {::},
  issn =         00037028,
  keywords =     {M-factors},
  mendeley-tags ={M-factors},
  month =        {sep},
}

@article{Czech2015,
  author =       {Czech, Kyle J. and Thompson, Blaise J. and Kain, Schuyler and
                  Ding, Qi and Shearer, Melinda J. and Hamers, Robert J. and
                  Jin, Song and Wright, John C.},
  title =        {{Measurement of Ultrafast Excitonic Dynamics of Few-Layer MoS
                  2 Using State-Selective Coherent Multidimensional
                  Spectroscopy}},
  journal =      {ACS Nano},
  volume =       9,
  number =       12,
  pages =        {12146--12157},
  year =         2015,
  doi =          {10.1021/acsnano.5b05198},
  url =          {http://pubs.acs.org/doi/abs/10.1021/acsnano.5b05198},
  abstract =     {We report the first coherent multidimensional spectroscopy
                  study of a MoS2 film. A four-layer sample of MoS2 was
                  synthesized on a silica substrate by a simplified sulfidation
                  reaction and characterized by absorption and Raman
                  spectroscopy, atomic force microscopy, and transmission
                  electron microscopy. State-selective coherent multidimensional
                  spectroscopy (CMDS) on the as-prepared MoS2 film resolved the
                  dynamics of a series of diagonal and cross-peak features
                  involving the spin-orbit split A and B excitonic states and
                  continuum states. The spectra are characterized by striped
                  features that are similar to those observed in CMDS studies of
                  quantum wells where the continuum states contribute strongly
                  to the initial excitation of both the diagonal and cross-peak
                  features, while the A and B excitonic states contributed
                  strongly to the final output signal. The strong contribution
                  from the continuum states to the initial excitation shows that
                  the continuum states are coupled to the A and B excitonic
                  states and that fast intraband relaxation is occurring on a
                  sub-70 fs time scale. A comparison of the CMDS excitation
                  signal and the absorption spectrum shows that the relative
                  importance of the continuum states is determined primarily by
                  their absorption strength. Diagonal and cross-peak features
                  decay with a 680 fs time constant characteristic of exciton
                  recombination and/or trapping. The short time dynamics are
                  complicated by coherent and partially coherent pathways that
                  become important when the excitation pulses are temporally
                  overlapped. In this region, the coherent dynamics create
                  diagonal features involving both the excitonic states and
                  continuum states, while the partially coherent pathways
                  contribute to cross-peak features.},
  file =         {::},
  issn =         {1936-0851},
  keywords =     {2D,2d,are layered,molybdenum sul fi de,molybdenum
                  sulfide,multidimensional,nonlinear,ransition metal
                  dichalcogenides,semiconductors with strong spin,such as mos
                  2,tmdcs,transition metal dichalcogenides,ultrafast
                  dynamics,{\`{a}}},
  month =        {dec},
  pmid =         26525496,
}

@article{Dai2009,
  author =       {Dai, Quanqin and Wang, Yingnan Yiding and Li, Xinbi and Zhang,
                  Yu and Pellegrino, Donald J. and Zhao, Muxun and Zou, Bo and
                  Seo, JaeTae and Wang, Yingnan Yiding and Yu, William W.},
  title =        {{Size-dependent composition and molar extinction coefficient
                  of PbSe semiconductor nanocrystals.}},
  journal =      {ACS nano},
  volume =       3,
  number =       6,
  pages =        {1518--24},
  year =         2009,
  doi =          {10.1021/nn9001616},
  url =          {http://www.ncbi.nlm.nih.gov/pubmed/19702314},
  abstract =     {Atomic compositions and molar extinction coefficients of PbSe
                  semiconductor nanocrystals were determined by atomic
                  absorption spectrometry, UV-vis-NIR spectrophotometry, and
                  transmission electron microscopy. The Pb/Se atomic ratio was
                  found to be size-dependent with a systematic excess of Pb
                  atoms in the PbSe nanocrystal system. Experimental results
                  indicated that the individual PbSe nanocrystal was
                  nonstoichiometric, consisting of a PbSe core and an extra
                  layer of Pb atoms. For these nonstoichiometric PbSe
                  semiconductor nanocrystals, we proposed a new computational
                  approach to calculate the total number of Pb and Se atoms in
                  different sized particles. This calculation played a key role
                  on the accurate determination of the strongly size-dependent
                  extinction coefficient, which followed a power law with an
                  exponent of approximately 2.5.},
  file =         {::},
  isbn =         {1936-0851},
  issn =         {1936-086X},
  keywords =     {Composition,Molar extinction coefficient,PbSe,Semiconductor
                  nanocrystal,Size dependence,informative,size-exciton
                  correlation},
  mendeley-tags ={informative},
  month =        {jun},
  pmid =         19435305,
}

@article{DeGeyter2012,
  author =       {{De Geyter}, Bram and Geiregat, Pieter and Gao, Yunan and {Ten
                  Cate}, Sybren and Houtepen, Arjan J. and Schins, Juleon M. and
                  {Van Thourhout}, Dries and Siebbeles, Laurens D A and Hens,
                  Zeger},
  title =        {{Broadband and picosecond intraband absorption in lead based
                  colloidal quantum dots}},
  journal =      {ACS Nano},
  number =       7,
  pages =        {6067--6074},
  year =         2012,
  doi =          {10.1109/ICTON.2012.6254469},
  abstract =     {Using femtosecond transient absorption spectroscopy we
                  demonstrate that lead chalcogenide nanocrystals show
                  considerable, photoinduced absorption (PA) in a broad
                  wavelength range just below the bandgap. The time-dependent
                  decay of the PA signal correlates with the recovery of the
                  band gap absorption, indicating that the same carriers are
                  involved. Based on this, we assign this PA signal to intraband
                  absorption, i.e., the excitation of photogenerated carriers
                  from the bottom of the conduction band or the top of the
                  valence band to higher energy levels in the conduction and
                  valence band continuum. We confirm our experiments with
                  tight-binding calculations. This broadband response in the
                  commercially interesting near to mid-infrared range is very
                  relevant for ultra high speed all optical signal processing.
                  We benchmark the performance with bulk-Si and
                  Si-nanocrystals.},
  file =         {::},
  isbn =         9781467322270,
  issn =         21627339,
  keywords =     {colloidal nanocrystals,free carrier absorption,intraband
                  absorption,lead chalcogenide,optical signal
                  processing,tight-binding,transient absorption spectroscopy},
  pmid =         22686663,
}

@article{DelCoso2004,
  author =       {del Coso, Ra{\'{u}}l and Solis, Javier},
  title =        {{Relation between nonlinear refractive index and third-order
                  susceptibility in absorbing media}},
  journal =      {Journal of the Optical Society of America B},
  volume =       21,
  number =       3,
  pages =        640,
  year =         2004,
  doi =          {10.1364/JOSAB.21.000640},
  url =          {http://www.opticsinfobase.org/abstract.cfm?URI=JOSAB-21-3-640
                  https://www.osapublishing.org/abstract.cfm?URI=josab-21-3-640},
  abstract =     {Expressions relating complex third-order optical
                  susceptibility ($\chi$(3)=$\chi$R(3)+i$\chi$I(3)) with
                  nonlinear refractive index (n2) and nonlinear absorption
                  coefficient ($\beta$) have been formulated that eliminate the
                  commonly used approximation of a negligible linear absorption
                  coefficient. The resulting equations do not show the
                  conventional linear dependence of $\chi$R(3) with n2 and
                  $\chi$I(3) with $\beta$. Nonlinear refraction and absorption
                  result instead from the interplay between the real and
                  imaginary parts of the first- and third-order susceptibilities
                  of the material. This effect is illustrated in the case of a
                  metal–dielectric nanocomposite for which n2 and $\beta$ values
                  were experimentally obtained by Z-scan measurements and for
                  which the use of the new formulas for $\chi$R(3) and
                  $\chi$I(3) yield a large correction and a sign reversal for
                  $\chi$I(3).},
  file =         {::},
  issn =         {0740-3224},
  month =        {mar},
  pmid =         220057300022,
}

@article{Gdor2012,
  author =       {Gdor, Itay and Sachs, Hanan and Roitblat, Avishy and
                  Strasfeld, David B. and Bawendi, Moungi G. and Ruhman,
                  Sanford},
  title =        {{Exploring exciton relaxation and multiexciton generation in
                  PbSe nanocrystals using hyperspectral near-IR probing.}},
  journal =      {ACS nano},
  volume =       6,
  number =       4,
  pages =        {3269--77},
  year =         2012,
  doi =          {10.1021/nn300184n},
  url =          {http://www.ncbi.nlm.nih.gov/pubmed/22390473},
  abstract =     {Hyperspectral femtosecond transient absorption spectroscopy is
                  employed to record exciton relaxation and recombination in
                  colloidal lead selenide (PbSe) nanocrystals in unprecedented
                  detail. Results obtained with different pump wavelengths and
                  fluences are scrutinized with regard to three issues: (1)
                  early subpicosecond spectral features due to "hot" excitons
                  are analyzed in terms of suggested underlying mechanisms; (2)
                  global kinetic analysis facilitates separation of the
                  transient difference spectra into single, double, and triple
                  exciton state contributions, from which individual band
                  assignments can be tested; and (3) the transient spectra are
                  screened for signatures of multiexciton generation (MEG) by
                  comparing experiments with excitation pulses both below and
                  well above the theoretical threshold for multiplication. For
                  the latter, a recently devised ultrafast pump-probe
                  spectroscopic approach is employed. Scaling sample
                  concentrations and pump pulse intensities inversely with the
                  extinction coefficient at each excitation wavelength overcomes
                  ambiguities due to direct multiphoton excitation,
                  uncertainties of absolute absorption cross sections, and low
                  signal levels. As observed in a recent application of this
                  method to InAs core/shell/shell nanodots, no sign of MEG was
                  detected in this sample up to photon energy 3.7 times the band
                  gap. Accordingly, numerous reports of efficient MEG in other
                  samples of PbSe suggest that the efficiency of this process
                  varies from sample to sample and depends on factors yet to be
                  determined.},
  file =         {::},
  isbn =         {1936-086X (Electronic)$\backslash$r1936-0851 (Linking)},
  issn =         {1936-086X},
  keywords =     {SADS,carrier multiplication,ciency in nanocrystals has,exciton
                  cooling,in accord,led,meg effi-,multiexciton
                  generation,quantum dots,the apparent enhancement of,ultrafast
                  spectroscopy},
  mendeley-tags ={SADS},
  month =        {apr},
  pmid =         22390473,
}

@article{Gdor2013a,
  author =       {Gdor, Itay and Yang, Chunfan and Yanover, Diana and Sachs,
                  Hanan and Lifshitz, Efrat and Ruhman, Sanford},
  title =        {{Novel Spectral Decay Dynamics of Hot Excitons in PbSe
                  Nanocrystals: A Tunable Femtosecond Pump–Hyperspectral Probe
                  Study}},
  journal =      {The Journal of Physical Chemistry C},
  volume =       117,
  number =       49,
  pages =        {26342--26350},
  year =         2013,
  doi =          {10.1021/jp409530z},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp409530z},
  abstract =     {Ultrafast exciton cooling in highly monodisperse PbSe
                  nanocrystals is followed with tunable pump?hyperspectral
                  near-IR probe spectroscopy. Unexpected kinetic and spectral
                  correlations between induced bleach and absorption features
                  are revealed, which are incompatible with standard models for
                  excited nanocrystal absorption. Interband optical excitation
                  immediately generates a sharp bleach feature near the 1Sh1Se
                  transition which is unchanged during exciton thermalization,
                  while pumping well above the band edge induces an intense
                  absorption at frequencies just below the band edge which
                  decays concurrently with a buildup of renewed absorbance at
                  the 1Ph1Pe peak during exciton cooling. Transient spectra of
                  hot single and double excitons are nearly indistinguishable,
                  arguing against the controversial involvement of Auger cooling
                  in the rapid dissipation of excess energy in excited PbSe QDs.
                  Finally, quantitative signal analysis shows no signs of
                  multiexciton generation up to photon energies four times the
                  sample band gap. Ultrafast exciton cooling in highly
                  monodisperse PbSe nanocrystals is followed with tunable
                  pump?hyperspectral near-IR probe spectroscopy. Unexpected
                  kinetic and spectral correlations between induced bleach and
                  absorption features are revealed, which are incompatible with
                  standard models for excited nanocrystal absorption. Interband
                  optical excitation immediately generates a sharp bleach
                  feature near the 1Sh1Se transition which is unchanged during
                  exciton thermalization, while pumping well above the band edge
                  induces an intense absorption at frequencies just below the
                  band edge which decays concurrently with a buildup of renewed
                  absorbance at the 1Ph1Pe peak during exciton cooling.
                  Transient spectra of hot single and double excitons are nearly
                  indistinguishable, arguing against the controversial
                  involvement of Auger cooling in the rapid dissipation of
                  excess energy in excited PbSe QDs. Finally, quantitative
                  signal analysis shows no signs of multiexciton generation up
                  to photon energies four times the sample band gap.},
  file =         {::},
  isbn =         1557522790,
  issn =         {1932-7447},
  month =        {dec},
}

@article{Gdor2015,
  author =       {Gdor, Itay and Shapiro, Arthur and Yang, Chunfan and Yanover,
                  Diana and Lifshitz, Efrat and Ruhman, Sanford},
  title =        {{Three-pulse femtosecond spectroscopy of PbSe nanocrystals: 1S
                  bleach nonlinearity and sub-band-edge excited-state absorption
                  assignment}},
  journal =      {ACS Nano},
  volume =       9,
  number =       2,
  pages =        {2138--2147},
  year =         2015,
  doi =          {10.1021/nn5074868},
  abstract =     {Above band-edge photo-excitation of PbSe nanocrystals induces
                  strong below band-gap absorption as well as a multi-phased
                  buildup of bleaching in the 1Se1Sh transition. The amplitudes
                  and kinetics of these features deviate from expectations based
                  on bi-exciton shifts and state filling which are the
                  mechanisms usually evoked to explain them. To clarify these
                  discrepancies, the same transitions are investigated here by
                  double-pump probe spectroscopy. Re-exciting in the below
                  band-gap induced absorption characteristic of hot excitons is
                  shown to produce additional excitons with high probability. In
                  addition, pump-probe experiments on a sample saturated with
                  single relaxed excitons proves that the resulting 1Se1Sh
                  bleach is not linear with the number of excitons per
                  nanocrystal. This finding holds for two samples differing
                  significantly in size, demonstrating its generality. Analysis
                  of the results suggest that below band edge induced absorption
                  in hot exciton states is due to excited state absorption and
                  not to shifted absorption of cold carriers, and that 1Se1Sh
                  bleach signals are not an accurate counter of sample excitons
                  when their distribution includes multi-exciton states.},
  file =         {::},
  isbn =         {1936-0851},
  issn =         {1936086X},
  keywords =     {exciton cooling,multiexciton generation,nanocrystals,quantum
                  dots,ultrafast spectroscopy},
}

@article{Gdor2015a,
  author =       {Gdor, Itay and Yanover, Dianna and Yang, Chunfan and Shapiro,
                  Arthur and Lifshitz, Efrat and Ruhman, Sanford},
  title =        {{Three Pulse Femtosecond Spectroscopy of PbSe Nano-Crystals ;
                  1S Bleach Nonlinearity and Sub Band-Edge Excited State
                  Absorption Assignment Three Pulse Femtosecond Spectroscopy of
                  PbSe nano-Crystals ; 1S Bleach Nonlinearity and Sub Band-edge
                  Excited State A}},
  journal =      {ACS Nano},
  pages =        {2--5},
  year =         2015,
  doi =          {10.1021/nn5074868},
  file =         {::},
}

@article{Geiregat2014,
  author =       {Geiregat, Pieter and Houtepen, Arjan J. and Justo, Yolanda and
                  Grozema, Ferdinand C. and {Van Thourhout}, Dries and Hens,
                  Zeger},
  title =        {{Coulomb Shifts upon Exciton Addition to Photoexcited PbS
                  Colloidal Quantum Dots}},
  journal =      {The Journal of Physical Chemistry C},
  volume =       118,
  number =       38,
  pages =        {22284--22290},
  year =         2014,
  doi =          {10.1021/jp505530k},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp505530k},
  abstract =     {Using ultrafast hyperspectral transient absorption (TA)
                  spectroscopy, we determine the biexciton addition energies in
                  PbS quantum dots (QDs) with different sizes when either a cold
                  or a hot electron−hole pair is added to a QD already
                  containing a cooled exciton. The observed dependence of this
                  so-called biexciton addition energy on the QD diameter and the
                  exciton energy can be rationalized by interpreting the
                  addition energies as the result of an imbalance in the Coulomb
                  interactions between the newly created carriers and the
                  carriers already present in a QD. The obtained results are
                  therefore relevant from both a fundamental and practical point
                  of view. They provide experimental data on Coulomb interaction
                  between charge carriers in confined semiconductors that can be
                  compared with theoretical estimates. Moreover, understanding
                  the way hot−cold biexciton addition energies influence the
                  transient absorption spectrum adds a new element to the
                  transient absorption toolbox for the optoelectronic properties
                  of colloidal QDs. ■ INTRODUCTION Colloidal semiconductor
                  nanocrystals or quantum dots (QDs) are an increasingly
                  prominent class of low-dimensional nanomaterials that combine
                  size-tunable electronic and optical properties with a
                  suitability for solution-based processing. Starting from
                  fundamental research and theoretical modeling on their unique
                  physical properties, QDs are now applied in a variety of
                  domains such as solar energy harvesting, photo-detection, and
                  light-emitting diodes or displays. 1−5 These applications
                  typically rely on the linear optical properties of QDs, i.e.,
                  light absorption by unexcited QDs and light emission by
                  radiative recombination in excited QDs. On the other hand,
                  various studies have shown that the spectral and
                  time-dependent properties of excited QDs can strongly enhance
                  the performance of QD-based devices in the above mention
                  applications or enable QDs to be used in completely different
                  applications. Quantum dots excited with photons having
                  energies exceeding twice that of the QD bandgap transition
                  can, for example, dissipate their excess energy by forming
                  biexcitons in a process called multiple exciton generation
                  (MEG) that can considerably enhance the short circuit current
                  of single junction, QD-based solar cells. 2,6−8 Controlling
                  the recombination rate of biexcitons by nonradiative Auger
                  processes allowed for the formation of blinking-free QDs and
                  facilitated the formation of QD-based lasers. 9,10 Moreover,
                  it was proven that excited QDs exhibit a broadband and
                  ultrafast photoinduced absorption related to intraband
                  transitions of either the excited electron or hole, which
                  could be used for optical modulation. 11,12},
  file =         {::;::},
  issn =         {1932-7447},
  month =        {sep},
}

@article{Gesuele2012,
  author =       {Gesuele, F and Sfeir, M Y and Murray, C B and Heinz, T F and
                  Wong, C W},
  title =        {{Biexcitonic Effects in Excited Ultrafast Supercontinuum
                  S{\aa}ectroscopy of Carrier Multiplication and Biexctionic
                  Effects in Excited States of PbS Quantum Dots}},
  journal =      {Nano letters},
  volume =       12,
  pages =        2658,
  year =         2012,
  file =         {::},
  keywords =     {1,2 the strong spatial,based-materials for third-generation
                  photovol-,carrier multiplication,confinement of electronic
                  wave,here is great interest,in the properties
                  of,multiple-exciton generation,qd,quantum dot,solar
                  cells,taics,ultrafast spectroscopy},
}

@article{Hogemann1996,
  author =       {H{\"{o}}gemann, Claudia and Pauchard, Marc and Vauthey, Eric},
  title =        {{Picosecond transient grating spectroscopy: The nature of the
                  diffracted spectrum}},
  journal =      {Review of Scientific Instruments},
  volume =       67,
  number =       10,
  pages =        {3449--3453},
  year =         1996,
  doi =          {10.1063/1.1147157},
  url =          {http://link.aip.org/link/RSINAK/v67/i10/p3449/s1{\&}Agg=doi
                  http://aip.scitation.org/doi/10.1063/1.1147157},
  file =         {::},
  issn =         {0034-6748},
  month =        {oct},
}

@article{Hutchings1992,
  author =       {Hutchings, D C and Sheik-Bahae, M and Hagan, D J and {Van
                  Stryland}, E W},
  title =        {{Kramers-Kronig relations in nonlinear optics}},
  journal =      {Optical and Quantum Electronics},
  volume =       24,
  number =       1,
  pages =        {1--30},
  year =         1992,
  doi =          {10.1007/BF01234275},
  url =
                  {http://dx.doi.org/10.1007/BF01234275{\%}5Cnhttp://www.springerlink.com/index/10.1007/BF01234275},
  abstract =     {We review dispersion relations, which relate the real part of
                  the optical susceptibility (refraction) to the imaginary part
                  (absorption). We derive and discuss these relations as applied
                  to nonlinear optical systems. It is shown that in the
                  nonlinear case, for self-action effects the correct form for
                  such dispersion relations is nondegenerate, i.e. it is
                  necessary to use multiple frequency arguments. Nonlinear
                  dispersion relations have been shown to be very useful as they
                  usually only require integration over a limited frequency
                  range (corresponding to frequencies at which the absorption
                  changes), unlike the conventional linear Kramers-Kr{\"{o}}nig
                  relation which requires integration over all absorbing
                  frequencies. Furthermore, calculation of refractive index
                  changes using dispersion relations is easier than a direct
                  calculation of the susceptibility, as transition rates (which
                  give absorption coefficients) are, in general, far easier to
                  calculate than the expectation value of the optical
                  polarization. Both resonant (generation of some excitation
                  that is long lived compared with an optical period) and
                  nonresonant ‘instantaneous' optical nonlinearities are
                  discussed, and it is shown that the nonlinear dispersion
                  relation has a common form and can be understood in terms of
                  the linear Kramers-Kr{\"{o}}nig relation applied to a new
                  system consisting of the material plus some ‘perturbation'. We
                  present several examples of the form of this external
                  perturbation, which can be viewed as the pump in a pump-probe
                  experiment. We discuss the two-level saturated atom model and
                  bandfilling in semiconductors among others for the resonant
                  case. For the nonresonant case some recent work is included
                  where the electronic nonlinear refractive coefficient,n2, is
                  determined from the nonlinear absorption processes of
                  two-photon absorption, Raman transitions and the a.c. Stark
                  effect. We also review how the dispersion relations can be
                  extended to give alternative forms for frequency summation
                  which, for example, allows the real and imaginary parts of?(2)
                  to be related.},
  file =         {::;::},
  isbn =         {0306-8919},
  issn =         03068919,
}

@article{Kang1997,
  author =       {Kang, Inuk and Wise, Frank W.},
  title =        {{Electronic structure and optical properties of PbS and PbSe
                  quantum dots}},
  journal =      {Journal of the Optical Society of America B},
  volume =       14,
  number =       7,
  pages =        1632,
  year =         1997,
  doi =          {10.1364/JOSAB.14.001632},
  url =
                  {http://www.opticsinfobase.org/abstract.cfm?URI=josab-14-7-1632},
  file =         {:C$\backslash$:/Users/Dan/AppData/Local/Mendeley Ltd./Mendeley
                  Desktop/Downloaded/Kang, Wise - 1997 - Electronic structure
                  and optical properties of PbS and PbSe quantum dots.pdf:pdf},
  issn =         {0740-3224},
  month =        {jul},
}

@article{Karki2013,
  author =       {Karki, Khadga J and Ma, Fei and Zheng, Kaibo and Zidek, Karel
                  and Mousa, Abdelrazek and Abdellah, Mohamed and Messing, Maria
                  E and Wallenberg, L Reine and Yartsev, Arkadi and Pullerits,
                  T{\~{o}}nu},
  title =        {{Multiple exciton generation in nano-crystals revisited:
                  consistent calculation of the yield based on pump-probe
                  spectroscopy.}},
  journal =      {Scientific reports},
  volume =       3,
  pages =        2287,
  year =         2013,
  doi =          {10.1038/srep02287},
  url =
                  {http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=3724175{\&}tool=pmcentrez{\&}rendertype=abstract},
  abstract =     {Multiple exciton generation (MEG) is a process in which more
                  than one exciton is generated upon the absorption of a high
                  energy photon, typically higher than two times the band gap,
                  in semiconductor nanocrystals. It can be observed
                  experimentally using time resolved spectroscopy such as the
                  transient absorption measurements. Quantification of the MEG
                  yield is usually done by assuming that the bi-exciton signal
                  is twice the signal from a single exciton. Herein we show that
                  this assumption is not always justified and may lead to
                  significant errors in the estimated MEG yields. We develop a
                  methodology to determine proper scaling factors to the signals
                  from the transient absorption experiments. Using the
                  methodology we find modest MEG yields in lead chalcogenide
                  nanocrystals including the nanorods.},
  file =         {::},
  issn =         {2045-2322},
  month =        {jan},
  pmid =         23887181,
}

@article{Kohler2014,
  author =       {Kohler, Daniel D. and Block, Stephen B. and Kain, Schuyler and
                  Pakoulev, Andrei V. and Wright, John C.},
  title =        {{Ultrafast Dynamics within the 1S Exciton Band of Colloidal
                  PbSe Quantum Dots Using Multiresonant Coherent
                  Multidimensional Spectroscopy}},
  journal =      {The Journal of Physical Chemistry C},
  volume =       118,
  number =       9,
  pages =        {5020--5031},
  year =         2014,
  doi =          {10.1021/jp412058u},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp412058u},
  file =         {::},
  issn =         {1932-7447},
  month =        {mar},
}

@article{Kohler2017,
  author =       {Kohler, Daniel D and Thompson, Blaise J and Wright, John C},
  title =        {{Frequency-domain coherent multidimensional spectroscopy when
                  dephasing rivals pulsewidth: Disentangling material and
                  instrument response}},
  journal =      {The Journal of Chemical Physics},
  volume =       147,
  number =       8,
  pages =        084202,
  year =         2017,
  doi =          {10.1063/1.4986069},
  url =          {http://dx.doi.org/10.1063/1.4986069
                  http://aip.scitation.org/toc/jcp/147/8
                  http://aip.scitation.org/doi/10.1063/1.4986069},
  abstract =     {Ultrafast spectroscopy is often collected in the mixed
                  frequency/time domain, where pulse durations are similar to
                  system dephasing times. In these experiments, expectations
                  derived from the familiar driven and impulsive limits are not
                  valid. This work simulates the mixed-domain four-wave mixing
                  response of a model system to develop expectations for this
                  more complex field-matter interaction. We explore frequency
                  and delay axes. We show that these line shapes are exquisitely
                  sensitive to excitation pulse widths and delays. Near pulse
                  overlap, the excitation pulses induce correlations that
                  resemble signatures of dynamic inhomogeneity. We describe
                  these line shapes using an intuitive picture that connects to
                  familiar field-matter expressions. We develop strategies for
                  distinguishing pulse-induced correlations from true system
                  inhomogeneity. These simulations provide a founda-tion for
                  interpretation of ultrafast experiments in the mixed domain.},
  file =         {::},
  issn =         {0021-9606},
  month =        {aug},
}

@article{Kraatz2014,
  author =       {Kraatz, Ingvar T and Booth, Matthew and Whitaker, Benjamin J
                  and Nix, Michael G D and Critchley, Kevin},
  title =        {{Sub-Bandgap Emission and Intraband Defect-Related
                  Excited-State Dynamics in Colloidal CuInS 2 /ZnS Quantum Dots
                  Revealed by Femtosecond Pump − Dump − Probe Spectroscopy}},
  year =         {2014},
  file =         {::},
}

@article{Lucarini2008,
  author =       {Lucarini, Valerio},
  title =        {{Response theory for equilibrium and non-equilibrium
                  statistical mechanics: Causality and generalized
                  kramers-kronig relations}},
  journal =      {Journal of Statistical Physics},
  volume =       131,
  number =       3,
  pages =        {543--558},
  year =         2008,
  doi =          {10.1007/s10955-008-9498-y},
  abstract =     {We consider the general response theory proposed by Ruelle for
                  describing the impact of small perturbations to the
                  non-equilibrium steady states resulting from Axiom A dynamical
                  systems. We show that the causality of the response functions
                  allows for writing a set of Kramers-Kronig relations for the
                  corresponding susceptibilities at all orders of nonlinearity.
                  Nonetheless, only a special class of observable
                  susceptibilities obey Kramers-Kronig relations. Specific
                  results are provided for arbitrary order harmonic response,
                  which allows for a very comprehensive Kramers-Kronig analysis
                  and the establishment of sum rules connecting the asymptotic
                  behavior of the susceptibility to the short-time response of
                  the system. These results generalize previous findings on
                  optical Hamiltonian systems and simple mechanical models, and
                  shed light on the general impact of considering the principle
                  of causality for testing self-consistency: the described
                  dispersion relations constitute unavoidable benchmarks for any
                  experimental and model generated dataset. In order to connect
                  the response theory for equilibrium and non equilibrium
                  systems, we rewrite the classical results by Kubo so that
                  response functions formally identical to those proposed by
                  Ruelle, apart from the measure involved in the phase space
                  integration, are obtained. We briefly discuss how these
                  results, taking into account the chaotic hypothesis, might be
                  relevant for climate research. In particular, whereas the
                  fluctuation-dissipation theorem does not work for
                  non-equilibrium systems, because of the non-equivalence
                  between internal and external fluctuations, Kramers-Kronig
                  relations might be more robust tools for the definition of a
                  self-consistent theory of climate change.},
  archivePrefix ={arXiv},
  arxivId =      {0710.0958},
  eprint =       {0710.0958},
  file =         {::},
  issn =         00224715,
  keywords =     {Axiom A dynamical systems,Chaotic hypothesis,Climate,Harmonic
                  generation,Kramers-Kronig relations,Kubo response
                  theory,Non-equilibrium steady states,Ruelle response
                  theory,SRB measure},
}

@article{Moreels2006,
  author =       {Moreels, I. and Hens, Z. and Kockaert, P. and Loicq, J. and
                  {Van Thourhout}, D.},
  title =        {{Spectroscopy of the nonlinear refractive index of colloidal
                  PbSe nanocrystals}},
  journal =      {Applied Physics Letters},
  volume =       89,
  number =       19,
  pages =        {0--4},
  year =         2006,
  doi =          {10.1063/1.2385658},
  abstract =     {A spectroscopic study of the optical nonlinearity of PbSe
                  colloidal solutions was performed with the Z-scan technique at
                  wavelength intervals of 1200-1350 and 1540-1750 nm. While
                  nonlinear absorption remains below the detection threshold,
                  the third order nonlinear refractive index n(2) shows clear
                  resonances, somewhat blueshifted relative to the exciton
                  transitions in the absorbance spectrum. The occurrence of
                  thermal effects is ruled out by time-resolved measurements. At
                  1.55 mu m, measured (resonant) n(2) values exceed typical bulk
                  semiconductor values by two orders of magnitude. At high
                  optical intensity, the refractive index change saturates,
                  indicating that statefilling lies at the origin of the
                  observed effect.},
  file =         {::},
  isbn =         {0003-6951},
  issn =         00036951,
}

@article{Moreels2007,
  author =       {Moreels, Iwan and Lambert, Karel and {De Muynck}, David and
                  Vanhaecke, Frank and Poelman, Dirk and Martins, Jos{\'{e}} C.
                  and Allan, Guy and Hens, Zeger},
  title =        {{Composition and Size-Dependent Extinction Coefficient of
                  Colloidal PbSe Quantum Dots}},
  journal =      {Chemistry of Materials},
  volume =       19,
  number =       25,
  pages =        {6101--6106},
  year =         2007,
  doi =          {10.1021/cm071410q},
  url =          {http://pubs.acs.org/doi/abs/10.1021/cm071410q},
  file =         {::},
  issn =         {0897-4756},
  keywords =     {reference,size-exciton correlation},
  mendeley-tags ={reference},
  month =        {dec},
}

@article{Moreels2008,
  author =       {Moreels, Iwan and Hens, Zeger},
  title =        {{On the interpretation of colloidal quantum-dot absorption
                  spectra.}},
  journal =      {Small (Weinheim an der Bergstrasse, Germany)},
  volume =       4,
  number =       11,
  pages =        {1866--8; author reply 1869--70},
  year =         2008,
  doi =          {10.1002/smll.200800068},
  url =          {http://www.ncbi.nlm.nih.gov/pubmed/18855972},
  file =         {::},
  issn =         {1613-6829},
  keywords =     {Absorption,Colloids,Colloids: chemistry,Quantum Dots,Spectrum
                  Analysis,Spectrum Analysis: methods},
  month =        {nov},
  pmid =         18855972,
}

@article{Moreels2009,
  author =       {Moreels, Iwan and Lambert, Karel and Muynck, David De and
                  Vanhaecke, Frank and Poelman, Dirk and Martins, Jos{\'{e}} C
                  and Allan, Guy and Hens, Zeger},
  title =        {{Size-Dependent Optical Properties of Colloidal {\{}PbS{\}}
                  Quantum Dots}},
  journal =      {ACS Nano},
  volume =       3,
  number =       10,
  pages =        {3023--3030},
  year =         2009,
  doi =          {10.1021/nn900863a},
  abstract =     {We quantitatively investigate the size-dependent optical
                  properties of colloidal {\{}PbS{\}} nanocrystals or quantum
                  dots (Qdots), by combining the Qdot absorbance spectra with
                  detailed elemental analysis of the Qdot suspensions. At high
                  energies, the molar extinction coefficient ?? increases with
                  the Qdot volume d3 and agrees with theoretical calculations
                  using the Maxwell???Garnett effective medium theory and bulk
                  values for the Qdot dielectric function. This demonstrates
                  that quantum confinement has no influence on ?? in this
                  spectral range, and it provides an accurate method to
                  calculate the Qdot concentration. Around the band gap, ?? only
                  increases with d1.3, and values are comparable to the ?? of
                  {\{}PbSe{\}} Qdots. The data are related to the oscillator
                  strength fif of the band gap transition and results agree well
                  with theoretical tight-binding calculations, predicting a
                  linear dependence of fif on d. For both {\{}PbS{\}} and
                  {\{}PbSe{\}} Qdots, the exciton lifetime ?? is calculated from
                  fif. We find values ranging between 1 and 3 ??s, in agreement
                  with experimental literature data from time-resolved
                  luminescence spectroscopy. Our results provide a thorough
                  general framework to calculate and understand the optical
                  properties of suspended colloidal quantum dots. Most
                  importantly, it highlights the significance of the local field
                  factor in these systems.},
  file =         {::},
  issn =         {1936-0851},
  keywords =     {exciton lifetime,extinction coefficient,lead
                  chalcogenide,molar,oscillator strength,pbse,semiconductor
                  nanocrystals},
}

@article{Nootz2011,
  author =       {Nootz, Gero and Padilha, Lazaro A. and Levina, Larissa and
                  Sukhovatkin, Vlad and Webster, Scott and Brzozowski, Lukasz
                  and Sargent, Edward H. and Hagan, David J. and {Van Stryland},
                  Eric W.},
  title =        {{Size dependence of carrier dynamics and carrier
                  multiplication in PbS quantum dots}},
  journal =      {Physical Review B - Condensed Matter and Materials Physics},
  volume =       83,
  number =       15,
  pages =        {1--7},
  year =         2011,
  doi =          {10.1103/PhysRevB.83.155302},
  abstract =     {The time dynamics of the photoexcited carriers and
                  carrier-multiplication efficiencies in PbS quantum dots (QDs)
                  are investigated. In particular, we report on the carrier
                  dynamics, including carrier multiplication, as a function of
                  QD size and compare them to the bulk value. We show that the
                  intraband 1P -{\textgreater} 1S decay becomes faster for
                  smaller QDs, in agreement with the absence of a phonon
                  bottleneck. Furthermore, as the size of the QDs decreases, the
                  energy threshold for carrier multiplication shifts from the
                  bulk value to higher energies. However, the energy threshold
                  shift is smaller than the band-gap shift and, therefore, for
                  the smallest QDs, the threshold approaches 2.35 E(g), which is
                  close to the theoretical energy conservation limit of twice
                  the band gap. We also show that the carrier-multiplication
                  energy efficiency increases with decreasing QD size. By
                  comparing to theoretical models, our results suggest that
                  impact ionization is sufficient to explain carrier
                  multiplication in QDs.},
  file =         {::},
  isbn =         {1098-0121},
  issn =         10980121,
}

@article{Okumura1999,
  author =       {Okumura, Ko and Tokmakoff, Andrei and Tanimura, Yoshitaka},
  title =        {{Two-dimensional line-shape analysis of photon-echo signal}},
  journal =      {Chemical Physics Letters},
  volume =       314,
  number =       {5-6},
  pages =        {488--495},
  year =         1999,
  doi =          {10.1016/S0009-2614(99)01173-2},
  url =          {http://linkinghub.elsevier.com/retrieve/pii/S0009261499011732},
  abstract =     {We analyze the two-dimensional (2D) line shape obtained by 2D
                  Fourier transforming the time-domain response of a photon-echo
                  signal as a function of the two coherence periods, t(1) and
                  t(3). The line shape obtained for a two-level system with
                  homogeneous and inhomogeneous broadening is shown to be
                  sensitive to the magnitude of both of these line-broadening
                  mechanisms. It is shown that the ellipticity of the 2D line
                  shape can be related to the ratio of homogeneous to
                  inhomogeneous broadening. (C) 1999 Elsevier Science B.V. All
                  rights reserved.},
  file =         {:C$\backslash$:/Users/Dan/AppData/Local/Mendeley Ltd./Mendeley
                  Desktop/Downloaded/Okumura, Tokmakoff, Tanimura - 1999 -
                  Two-dimensional line-shape analysis of photon-echo
                  signal.pdf:pdf},
  isbn =         {0009-2614},
  issn =         00092614,
  keywords =     {3rd-order,dynamics,glasses,phase,probes,spectroscopy},
  month =        {dec},
}

@article{Olivero1977,
  author =       {Olivero, J.J. and Longbothum, R.L.},
  title =        {{Empirical fits to the voigt line width: A brief review}},
  journal =      {J. Quant. Spectrosc. Radiat. Transfer},
  volume =       17,
  pages =        {233--236},
  year =         1977,
  file =         {::},
}

@article{Omari2012,
  author =       {Omari, Abdoulghafar and Moreels, Iwan and Masia, Francesco and
                  Langbein, Wolfgang and Borri, Paola and {Van Thourhout}, Dries
                  and Kockaert, Pascal and Hens, Zeger},
  title =        {{Role of interband and photoinduced absorption in the
                  nonlinear refraction and absorption of resonantly excited PbS
                  quantum dots around 1550 nm}},
  journal =      {Physical Review B},
  volume =       85,
  number =       11,
  pages =        115318,
  year =         2012,
  doi =          {10.1103/PhysRevB.85.115318},
  url =          {http://link.aps.org/doi/10.1103/PhysRevB.85.115318},
  file =         {::},
  issn =         {1098-0121},
  month =        {mar},
}

@article{Pang1991,
  author =       {Pang, Yang and Samoc, Marek and Prasad, Paras N.},
  title =        {{Third‐order nonlinearity and two‐photon‐induced molecular
                  dynamics: Femtosecond time‐resolved transient absorption, Kerr
                  gate, and degenerate four‐wave mixing studies in poly ( p
                  ‐phenylene vinylene)/sol‐gel silica film}},
  journal =      {The Journal of Chemical Physics},
  volume =       94,
  number =       8,
  pages =        {5282--5290},
  year =         1991,
  doi =          {10.1063/1.460512},
  url =
                  {http://scitation.aip.org/content/aip/journal/jcp/94/8/10.1063/1.460512
                  http://aip.scitation.org/doi/10.1063/1.460512},
  abstract =     {Femtosecond response and relaxation of the third-order optical
                  nonlinearity in a newly developed poly (p-phenylene
                  vinylene)/sol-gel silica composite are investigated by time-
                  resolved forward wave degenerate four-wave mixing, Kerr gate,
                  and transient absorption techniques using 60 fs pulses at 620
                  nm. Using a theoretical description of two- and four-wave
                  mixing in optically nonlinear media, it is shown that the
                  results obtained from simultaneous use of these techniques
                  yield valuable information on the real and imaginary
                  components of the third-order susceptibility. In the composite
                  material investigated here, the imaginary component is derived
                  from the presence of a two-photon resonance at the wavelength
                  of 620 nm used for the present study. This two-photon
                  resonance is observed as transient absorption of the probe
                  beam induced by the presence of a strong pump beam. It also
                  provides fifth-order nonlinear response both in transient
                  absorption and in degenerate four-wave mixing. The fifth-
                  order contributions are derived from the two-photon generated
                  excited species which can absorb at the measurement wavelength
                  and therefore modify both the absorption coefficient and the
                  refractive index of the medium.},
  file =         {::},
  issn =         {0021-9606},
  month =        {apr},
}

@article{Peterson2007,
  author =       {Peterson, JJ and Huang, Libai and Delerue, C. and Allan, Guy},
  title =        {{Uncovering forbidden optical transitions in PbSe
                  nanocrystals}},
  journal =      {nano Letters},
  year =         2007,
  url =          {http://pubs.acs.org/doi/abs/10.1021/nl072487g},
  file =         {:C$\backslash$:/Users/Dan/AppData/Local/Mendeley Ltd./Mendeley
                  Desktop/Downloaded/Peterson et al. - 2007 - Uncovering
                  forbidden optical transitions in PbSe nanocrystals.pdf:pdf},
  keywords =     {1P exciton,2 photon absorption,new,relevant},
  mendeley-tags ={new,relevant},
}

@article{Price2015,
  author =       {Price, Michael B. and Butkus, Justinas and Jellicoe, Tom C.
                  and Sadhanala, Aditya and Briane, Anouk and Halpert, Jonathan
                  E. and Broch, Katharina and Hodgkiss, Justin M. and Friend,
                  Richard H. and Deschler, Felix},
  title =        {{Hot-carrier cooling and photoinduced refractive index changes
                  in organic–inorganic lead halide perovskites}},
  journal =      {Nature Communications},
  volume =       6,
  number =       {May},
  pages =        8420,
  year =         2015,
  doi =          {10.1038/ncomms9420},
  url =          {http://dx.doi.org/10.1038/ncomms9420
                  http://www.nature.com/doifinder/10.1038/ncomms9420},
  archivePrefix ={arXiv},
  arxivId =      {arXiv:1504.07508},
  eprint =       {arXiv:1504.07508},
  file =         {::},
  issn =         {2041-1723},
  publisher =    {Nature Publishing Group},
}

@article{Schaller2003,
  author =       {Schaller, Richard D and Petruska, M. a. and Klimov, Victor I.},
  title =        {{Tunable Near-Infrared Optical Gain and Amplified Spontaneous
                  Emission Using PbSe Nanocrystals}},
  journal =      {The Journal of Physical Chemistry B},
  volume =       107,
  number =       50,
  pages =        {13765--13768},
  year =         2003,
  doi =          {10.1021/jp0311660},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp0311660},
  file =         {::;::},
  issn =         {1520-6106},
  month =        {dec},
}

@article{Schins2009,
  author =       {Schins, Juleon and Trinh, M. and Houtepen, Arjan and
                  Siebbeles, Laurens},
  title =        {{Probing formally forbidden optical transitions in PbSe
                  nanocrystals by time- and energy-resolved transient absorption
                  spectroscopy}},
  journal =      {Physical Review B},
  volume =       80,
  number =       3,
  pages =        035323,
  year =         2009,
  doi =          {10.1103/PhysRevB.80.035323},
  url =          {http://link.aps.org/doi/10.1103/PhysRevB.80.035323},
  file =         {::},
  issn =         {1098-0121},
  month =        {jul},
}

@article{Svirko1999,
  author =       {{P. Svirko}, Yuri and Shirane, Masayuki and Suzuura, Hidekatsu
                  and Kuwata-Gonokami, Makoto},
  title =        {{Four-Wave Mixing Theory at the Excitonic Resonance: Weakly
                  Interacting Boson Model}},
  journal =      {Journal of the Physical Society of Japan},
  volume =       68,
  number =       2,
  pages =        {674--682},
  year =         1999,
  doi =          {10.1143/JPSJ.68.674},
  url =          {http://journals.jps.jp/doi/10.1143/JPSJ.68.674},
  file =         {::},
  issn =         {0031-9015},
  keywords =     {Exciton,Four-particle correlation,Four-wave mixing,Normal mode
                  splitting,Semiconductor microcavity},
  month =        {feb},
}

@article{Trinh2008,
  author =       {Trinh, M Tuan and Houtepen, Arjan J and Schins, Juleon M and
                  Piris, Jorge and Siebbeles, Laurens D a},
  title =        {{Nature of the second optical transition in PbSe
                  nanocrystals.}},
  journal =      {Nano letters},
  volume =       8,
  number =       7,
  pages =        {2112--7},
  year =         2008,
  doi =          {10.1021/nl8010963},
  url =          {http://www.ncbi.nlm.nih.gov/pubmed/18510369},
  abstract =     {The second peak in the optical absorption spectrum of PbSe
                  nanocrystals is arguably the most discussed optical transition
                  in semiconductor nanocrystals. Ten years of scientific debate
                  have produced many theoretical and experimental claims for the
                  assignment of this feature as the 1P e1P h as well as the 1S
                  h,e1P e,h transitions. We studied the nature of this
                  absorption feature by pump-probe spectroscopy, exactly
                  controlling the occupation of the states involved, and present
                  conclusive evidence that the optical transition involves
                  neither 1S e nor 1S h states. This suggests that it is the 1P
                  h1P e transition that gives rise to the second peak in the
                  absorption spectrum of PbSe nanocrystals.},
  file =         {::},
  issn =         {1530-6984},
  month =        {jul},
  pmid =         18510369,
}

@article{Trinh2013,
  author =       {Trinh, M. Tuan and Sfeir, Matthew Y. and Choi, Joshua J. and
                  Owen, Jonathan S. and Zhu, Xiaoyang},
  title =        {{A Hot Electron–Hole Pair Breaks the Symmetry of a
                  Semiconductor Quantum Dot}},
  journal =      {Nano Letters},
  volume =       13,
  number =       12,
  pages =        {6091--6097},
  year =         2013,
  doi =          {10.1021/nl403368y},
  url =          {http://pubs.acs.org/doi/abs/10.1021/nl403368y},
  file =         {::},
  issn =         {1530-6984},
  keywords =     {google the phrase,hot carriers,nanocrystals or,near the
                  bandgap is,now well-,one,ptical excitation of
                  semiconductor,qds,quantum dots,selection rules,stark
                  effect,symmetry breaking,transient absorption,understood},
  month =        {dec},
}

@article{Wehrenberg2002,
  author =       {Wehrenberg, Brian L. and Wang, Congjun and Guyot-Sionnest,
                  Philippe},
  title =        {{Interband and Intraband Optical Studies of PbSe Colloidal
                  Quantum Dots}},
  journal =      {The Journal of Physical Chemistry B},
  volume =       106,
  number =       41,
  pages =        {10634--10640},
  year =         2002,
  doi =          {10.1021/jp021187e},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp021187e},
  file =         {::},
  issn =         {1520-6106},
  month =        {oct},
}

@article{Wise2000,
  author =       {Wise, Frank W.},
  title =        {{Lead salt quantum dots: the limit of strong quantum
                  confinement.}},
  journal =      {Accounts of chemical research},
  volume =       33,
  number =       11,
  pages =        {773--80},
  year =         2000,
  url =          {http://www.ncbi.nlm.nih.gov/pubmed/11087314},
  abstract =     {Nanocrystals or quantum dots of the IV-VI semiconductors PbS,
                  PbSe, and PbTe provide unique properties for investigating the
                  effects of strong confinement on electrons and phonons. The
                  degree of confinement of charge carriers can be many times
                  stronger than in most II-VI and III-V semiconductors, and lead
                  salt nanostructures may be the only materials in which the
                  electronic energies are determined primarily by quantum
                  confinement. This Account briefly reviews recent research on
                  lead salt quantum dots.},
  file =         {:C$\backslash$:/Users/Dan/AppData/Local/Mendeley Ltd./Mendeley
                  Desktop/Downloaded/Wise - 2000 - Lead salt quantum dots the
                  limit of strong quantum confinement.pdf:pdf},
  issn =         {0001-4842},
  keywords =     {Crystallization,Electrochemistry,Lead,Lead:
                  chemistry,Semiconductors,Temperature},
  month =        {nov},
  pmid =         11087314,
}

@article{Yang2015,
  author =       {Yang, Ye and Yan, Yong and Yang, Mengjin and Choi, Sukgeun and
                  Zhu, Kai and Luther, Joseph M and Beard, Matthew C},
  title =        {{Low surface recombination velocity in}},
  journal =      {Nature Communications},
  volume =       6,
  pages =        {1--6},
  year =         2015,
  doi =          {10.1038/ncomms8961},
  url =          {http://dx.doi.org/10.1038/ncomms8961},
  file =         {::},
  publisher =    {Nature Publishing Group},
}

@article{Yang2017,
  author =       {Yang, Ye and Yang, Mengjin and Moore, David?T. and Yan, Yong
                  and Miller, Elisa?M. and Zhu, Kai and Beard, Matthew?C.},
  title =        {{Top and bottom surfaces limit carrier lifetime in lead iodide
                  perovskite films}},
  journal =      {Nature Energy},
  volume =       2,
  number =       2,
  pages =        16207,
  year =         2017,
  doi =          {10.1038/nenergy.2016.207},
  url =          {http://www.nature.com/articles/nenergy2016207},
  abstract =     {Carrier recombination at defects is detrimental to the
                  performance of solar energy conversion systems, including
                  solar cells and photoelectrochemical devices. Point defects
                  are localized within the bulk crystal while extended defects
                  occur at surfaces and grain boundaries. If not properly
                  managed, surfaces can be a large source of carrier
                  recombination. Separating surface carrier dynamics from bulk
                  and/or grain-boundary recombination in thin films is
                  challenging. Here, we employ transient reflection spectroscopy
                  to measure the surface carrier dynamics in methylammonium lead
                  iodide perovskite polycrystalline films. We find that surface
                  recombination limits the total carrier lifetime in perovskite
                  polycrystalline thin films, meaning that recombination inside
                  grains and/or at grain boundaries is less important than top
                  and bottom surface recombination. The surface recombination
                  velocity in polycrystalline films is nearly an order of
                  magnitude smaller than that in single crystals, possibly due
                  to unintended surface passivation of the films during
                  synthesis.},
  file =         {::},
  issn =         {2058-7546},
  month =        {jan},
}

@article{Yurs2011,
  author =       {Yurs, Lena A and Block, Stephen B and Pakoulev, Andrei V. and
                  Selinsky, Rachel S. and Jin, Song and Wright, John},
  title =        {{Multiresonant Coherent Multidimensional Electronic
                  Spectroscopy of Colloidal PbSe Quantum Dots}},
  journal =      {The Journal of Physical Chemistry C},
  volume =       115,
  number =       46,
  pages =        {22833--22844},
  year =         2011,
  doi =          {10.1021/jp207273x},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp207273x},
  file =         {::},
  issn =         {1932-7447},
  month =        {nov},
}

@article{Yurs2012,
  author =       {Yurs, Lena A and Block, Stephen B and Pakoulev, Andrei V. and
                  Selinsky, Rachel S. and Jin, Song and Wright, John},
  title =        {{Spectral Isolation and Measurement of Surface-Trapped State
                  Multidimensional Nonlinear Susceptibility in Colloidal Quantum
                  Dots}},
  journal =      {The Journal of Physical Chemistry C},
  volume =       116,
  number =       9,
  pages =        {5546--5553},
  year =         2012,
  doi =          {10.1021/jp3014139},
  url =          {http://pubs.acs.org/doi/abs/10.1021/jp3014139},
  file =         {::},
  issn =         {1932-7447},
  month =        {mar},
}