aboutsummaryrefslogtreecommitdiff
path: root/PEDOT:PSS
diff options
context:
space:
mode:
Diffstat (limited to 'PEDOT:PSS')
-rw-r--r--PEDOT:PSS/beam waist.pngbin0 -> 82375 bytes
-rw-r--r--PEDOT:PSS/chapter.tex170
-rw-r--r--PEDOT:PSS/compare 2D.pngbin0 -> 1440621 bytes
-rw-r--r--PEDOT:PSS/compare slices.pngbin0 -> 372559 bytes
-rw-r--r--PEDOT:PSS/compare.pngbin0 -> 484738 bytes
-rw-r--r--PEDOT:PSS/delay space.pngbin0 -> 117602 bytes
-rw-r--r--PEDOT:PSS/excitation pulse spectra.pngbin0 -> 112000 bytes
-rw-r--r--PEDOT:PSS/linear.pngbin0 -> 178770 bytes
-rw-r--r--PEDOT:PSS/main.pngbin0 -> 445523 bytes
-rw-r--r--PEDOT:PSS/mask.pngbin0 -> 143220 bytes
-rw-r--r--PEDOT:PSS/overtraces.pngbin0 -> 368434 bytes
-rw-r--r--PEDOT:PSS/peak shift.pngbin0 -> 187305 bytes
-rw-r--r--PEDOT:PSS/processed.pngbin0 -> 1960170 bytes
-rw-r--r--PEDOT:PSS/raw.pngbin0 -> 710687 bytes
-rw-r--r--PEDOT:PSS/substrate.pngbin0 -> 384158 bytes
-rw-r--r--PEDOT:PSS/traces.pngbin0 -> 804127 bytes
16 files changed, 169 insertions, 1 deletions
diff --git a/PEDOT:PSS/beam waist.png b/PEDOT:PSS/beam waist.png
new file mode 100644
index 0000000..1e99afc
--- /dev/null
+++ b/PEDOT:PSS/beam waist.png
Binary files differ
diff --git a/PEDOT:PSS/chapter.tex b/PEDOT:PSS/chapter.tex
index c7dc807..9138972 100644
--- a/PEDOT:PSS/chapter.tex
+++ b/PEDOT:PSS/chapter.tex
@@ -1 +1,169 @@
-\chapter{PEDOT:PSS} \ No newline at end of file
+\chapter{PEDOT:PSS}
+
+\section{Introduction}
+
+Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is a transparent, electrically
+conductive (up to 4380 S cm$^{-1}$ \cite{KimNara2013a}) polymer. %
+It has found widespread use as a flexible, cheap alternative to inorganic transparent electrodes
+such as indium tin oxide. %
+
+As a polymer, PEDOT:PSS implicitly contains a large amount of structural inhomogeneity. %
+On top of this, PEDOT:PSS is a two component material, composed of PEDOT (low molecular weight,
+p-doped, highly conductive) and PSS (high molecular-weight, insulating, stabilizing). %
+These two components segment into domains of conductive and non-conductive material, leading to
+even more structural inhomogeneity. %
+Nonlinear spectroscopy may be able to shed light on the microscopic environment of electronic
+states within PEDOT:PSS. %
+
+\section{Background}
+
+Complex microstructure:
+\begin{enumerate}
+ \item PEDOT oligomers (6---18-mers)
+ \item these oligomers $\pi$-stack to form small nanocrystalites, 3 to 14 oligomers for pristine
+ films to as many as 13---14 oligomers for more conductive solvent treated films
+ \item nanocrystallites then arrange into globular conductive particles in a pancakge-like shape
+ \item these particles themselves are then linked via PSS-rich domains and assembled into
+ nanofibril geometry akin to a string of pearls
+ \item nanofibrils interweave to form thin films, with PSS capping layer at surface
+\end{enumerate}
+
+Prior spectroscopy (absorption anisotropy, X-ray scattering, condutivity). %
+
+% TODO: absorption spectrum of thin film
+
+Broad in the infrared due to midgap states created during doping from charge-induced lattice
+relaxations. %
+These electronic perturbations arise from injected holes producing a quinoidal distortion spread
+over 4-5 monomers of the CP aromatic backbone, collectively called a polaron. %
+Energetically favorable to be spin-silent bipolaron. %
+
+\section{Methods}
+
+PEDOT:PSS (Orgacon Dry, Sigma Aldrich) was dropcast onto a glass microscope slide at 1 mg/mL at a
+tilt to ensure homogeneous film formation. %
+The sample was heated at 100 $^\circ$C for $\sim$15 min to evaporate water. %
+
+An ultrafast oscillator (Spectra-Physics Tsunami) was used to prepare $\sim$35 fs seed pulses. %
+These were amplified (Spectra-Physics Spitfire Pro XP, 1 kHz), split, and converted into 1300 nm 40
+fs pulses using two separate optical parametric amplifiers (Light Conversion TOPAS-C): ``OPA1'' and
+``OPA2''. %
+Pulses from OPA2 were split again, for a total of three excitation pulses: $\omega_1$, $\omega_2$
+and $\omega_{2^\prime}$. %
+These were passed through motorized (Newport MFA-CC) retroreflectors to control their relative
+arrival time (``delay'') at the sample: $\tau_{21} = \tau_2 - \tau_1$ and $\tau_{22^\prime} =
+\tau_2 - \tau_{2^\prime}$. The three excitation pulses were focused into the sample in a $1^\circ$
+right-angle isoceles triange, as in the BOXCARS configuration. \cite{EckbrethAlanC1978a} %
+Each excitation beam was 67 nJ focused into a 375 $\mathsf{\mu m}$ symmetric Gaussian mode for an
+intensity of 67 $\mathsf{\mu J / cm^2}$. %
+A new beam, emitted coherently from the sample, was isolated with apertures and passed into a
+monochromator (HORIBA Jobin Yvon MicroHR, 140 mm focal length) with a visible grating (500 nm blaze
+300 groves per mm). %
+The monochromator was set to pass all colors (0 nm, 250 $\mathsf{\mu m}$ slits) to keep the
+measurement impulsive. %
+Signal was detected using an InSb photodiode (Teledyne Judson J10D-M204-R01M-3C-SP28). %
+Four wave mixing was isolated from excitation scatter using dual chopping and digital signal
+processing. %
+
+\section{Transmittance and reflectance}
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/linear"}
+ \caption[PEDOT:PSS transmission and reflectance spectra.]{
+ Thin film spectra.
+ Transmission, reflectance, and extinction spectrum of the thin film used in this work. %
+ Extinction is $\log_{10}{\mathsf{(transmission)}}$. %
+ }
+ \label{fig:PEDOTPSS_linear}
+\end{figure}
+\clearpage}
+
+\autoref{fig:PEDOTPSS_linear} shows the transmission, reflectance, and extinction spectrum of the
+thin film used in this work. %
+
+\section{Three-pulse echo spectroscopy}
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/mask"}
+ \caption[PEDOT:PSS 3PE phase matching mask.]{
+ Phase matching mask used in this experiment.
+ Each successive ring subtends 1 degree, such that the excitation pulses are each angled one
+ degree relative to the mask center.
+ The two stars mark the two output poyntings detected in this work.
+ }
+ \label{fig:PEDOTPSS_mask}
+\end{figure}
+\clearpage}
+
+Two dimensional $\tau_{21}, \tau_{22^\prime}$ scans were taken for two phase matching
+configurations: (1) $k_{\mathsf{out}} = k_1 - k_2 + k_{2^\prime}$ (3PE) and (2) $k_{\mathsf{out}} =
+k_1 + k_2 - k_{2^\prime}$ (3PE*). %
+The rephasing and nonrephasing pathways exchange their time dependance between these two
+configurations. %
+Comparing both pathways, rephasing-induced peak shifts can be extracted as in 3PE. [CITE] %
+All data was modeled using numerical integration of the Liouville-von Numann equation. %
+
+Continuously variable ND filters (THORLABS NDC-100C-4M, THORLABS NDL-10C-4) were used to ensure
+that all three excitation pulse powers were equal within measurement error. %
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/raw"}
+ \caption[PEDOT:PSS 3PE raw data.]{
+ CAPTION TODO
+ }
+ \label{fig:PEDOTPSS_raw}
+\end{figure}
+\clearpage}
+
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/processed"}
+ \caption[PEDOT:PSS 3PE processed data.]{
+ CAPTION TODO
+ }
+ \label{fig:PEDOTPSS_processed}
+\end{figure}
+\clearpage}
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/delay_space"}
+ \caption[PEDOT:PSS 3PE delay space.]{
+ CAPTION TODO
+ }
+ \label{fig:PEDOTPSS_delay_space}
+\end{figure}
+\clearpage}
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/traces"}
+ \caption[PEDOT:PSS 3PE traces.]{
+ CAPTION TODO
+ }
+ \label{fig:PEDOTPSS_traces}
+\end{figure}
+\clearpage}
+
+\afterpage{
+\begin{figure}
+ \centering
+ \includegraphics[width=0.5\linewidth]{"PEDOT:PSS/overtraces"}
+ \caption[PEDOT:PSS 3PE traces.]{
+ CAPTION TODO
+ }
+ \label{fig:PEDOTPSS_overtraces}
+\end{figure}
+\clearpage}
+
+\section{Frequency-domain transient grating spectroscopy} \ No newline at end of file
diff --git a/PEDOT:PSS/compare 2D.png b/PEDOT:PSS/compare 2D.png
new file mode 100644
index 0000000..e42cb42
--- /dev/null
+++ b/PEDOT:PSS/compare 2D.png
Binary files differ
diff --git a/PEDOT:PSS/compare slices.png b/PEDOT:PSS/compare slices.png
new file mode 100644
index 0000000..8433b81
--- /dev/null
+++ b/PEDOT:PSS/compare slices.png
Binary files differ
diff --git a/PEDOT:PSS/compare.png b/PEDOT:PSS/compare.png
new file mode 100644
index 0000000..2cfd095
--- /dev/null
+++ b/PEDOT:PSS/compare.png
Binary files differ
diff --git a/PEDOT:PSS/delay space.png b/PEDOT:PSS/delay space.png
new file mode 100644
index 0000000..1fed3f6
--- /dev/null
+++ b/PEDOT:PSS/delay space.png
Binary files differ
diff --git a/PEDOT:PSS/excitation pulse spectra.png b/PEDOT:PSS/excitation pulse spectra.png
new file mode 100644
index 0000000..01d2426
--- /dev/null
+++ b/PEDOT:PSS/excitation pulse spectra.png
Binary files differ
diff --git a/PEDOT:PSS/linear.png b/PEDOT:PSS/linear.png
new file mode 100644
index 0000000..7c48bed
--- /dev/null
+++ b/PEDOT:PSS/linear.png
Binary files differ
diff --git a/PEDOT:PSS/main.png b/PEDOT:PSS/main.png
new file mode 100644
index 0000000..e1f10d8
--- /dev/null
+++ b/PEDOT:PSS/main.png
Binary files differ
diff --git a/PEDOT:PSS/mask.png b/PEDOT:PSS/mask.png
new file mode 100644
index 0000000..418e928
--- /dev/null
+++ b/PEDOT:PSS/mask.png
Binary files differ
diff --git a/PEDOT:PSS/overtraces.png b/PEDOT:PSS/overtraces.png
new file mode 100644
index 0000000..767517c
--- /dev/null
+++ b/PEDOT:PSS/overtraces.png
Binary files differ
diff --git a/PEDOT:PSS/peak shift.png b/PEDOT:PSS/peak shift.png
new file mode 100644
index 0000000..42e7b43
--- /dev/null
+++ b/PEDOT:PSS/peak shift.png
Binary files differ
diff --git a/PEDOT:PSS/processed.png b/PEDOT:PSS/processed.png
new file mode 100644
index 0000000..32b210c
--- /dev/null
+++ b/PEDOT:PSS/processed.png
Binary files differ
diff --git a/PEDOT:PSS/raw.png b/PEDOT:PSS/raw.png
new file mode 100644
index 0000000..58cef4a
--- /dev/null
+++ b/PEDOT:PSS/raw.png
Binary files differ
diff --git a/PEDOT:PSS/substrate.png b/PEDOT:PSS/substrate.png
new file mode 100644
index 0000000..2a5fe49
--- /dev/null
+++ b/PEDOT:PSS/substrate.png
Binary files differ
diff --git a/PEDOT:PSS/traces.png b/PEDOT:PSS/traces.png
new file mode 100644
index 0000000..7ffc5d0
--- /dev/null
+++ b/PEDOT:PSS/traces.png
Binary files differ