diff options
author | Blaise Thompson <blaise@untzag.com> | 2018-04-05 17:29:20 -0500 |
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committer | Blaise Thompson <blaise@untzag.com> | 2018-04-05 17:29:20 -0500 |
commit | ff2e66aeef80259d60df46261305d387ad604baa (patch) | |
tree | f91f23f9b086c067735e47364065cee464a9bf9e /spectroscopy | |
parent | f9f611827e436063d77924fbbd64fa0628d584e1 (diff) |
2018-04-05 17:29
Diffstat (limited to 'spectroscopy')
-rw-r--r-- | spectroscopy/auto/chapter.el | 3 | ||||
-rw-r--r-- | spectroscopy/chapter.tex | 88 |
2 files changed, 17 insertions, 74 deletions
diff --git a/spectroscopy/auto/chapter.el b/spectroscopy/auto/chapter.el index f316ae6..b067440 100644 --- a/spectroscopy/auto/chapter.el +++ b/spectroscopy/auto/chapter.el @@ -7,7 +7,6 @@ "spc:fig:trive_off_diagonal" "spc:fig:trive_population_transfer" "fig:ta_and_tr_setup" - "eq:ta_complete" - "eq:generic")) + "eq:ta_complete")) :latex) diff --git a/spectroscopy/chapter.tex b/spectroscopy/chapter.tex index 030edd5..2cf088b 100644 --- a/spectroscopy/chapter.tex +++ b/spectroscopy/chapter.tex @@ -145,10 +145,19 @@ WMEL diagrams are drawn using the following rules. % \item Output is represented as a solid wavy line.
\end{denumerate}
+Representative WMELs can be found in Figures [xxxxxx]. %
+
% TODO: representative WMEL?
\section{Types of spectroscopy} % ================================================================
+Scientists have come up with many ways of exploiting light-matter interaction for measurement
+purposes. %
+This section discusses several of these strategies. %
+I start broadly, by comparing and contrasting differences across categories of spectroscopies. %
+I then go into relevant detail regarding a few experiments that are particularly relevant in this
+dissertation. %
+
\subsection{Linear vs multidimensional} % --------------------------------------------------------
This derivation adapted from \textit{Optical Processes in Semiconductors} by Jacques I. Pankove
@@ -170,6 +179,8 @@ To extend reflectivity to a differential measurement Nonlinear spectroscopy relies upon higher-order terms in the light-matter interaction. In a generic
system, each term is roughly ten times smaller than the last. % TODO: cite?
+TODO: Basic ``advantage of dimensionality'' figure.
+
\subsection{Homodyne vs heterodyne} % ------------------------------------------------------------
Two kinds of spectroscopies: 1) heterodyne 2) homodyne.
@@ -182,6 +193,8 @@ This literally means that homodyne signals go as the square of heterodyne signal mean when we say that homodyne signals are intensity level and heterodyne signals are amplitude
level.
+Homodyne dynamics go faster: cite Darien correction
+
\subsection{Frequency vs time domain} % ----------------------------------------------------------
Time domain techniques become more and more difficult when large frequency bandwidths are
@@ -203,6 +216,8 @@ Since time-domain pulses in-fact possess all colors in them they cannot be trust perturbative fluence. %
See that paper that Natalia presented... %
+See Paul's dissertation
+
\subsection{Transient grating} % -----------------------------------------------------------------
Triply Electronically Enhanced (TrEE) spectroscopy has become the workhorse homodyne-detected 4WM
@@ -318,11 +333,10 @@ expression for $\Delta A$ that only depends on my eight measurables. % \Delta A = - \log_{10} \left(\frac{C_\mathrm{T}(V_\mathrm{T} + V_{\Delta\mathrm{T}}) + C_\mathrm{R}(V_\mathrm{R} + V_{\Delta\mathrm{R}})}{C_\mathrm{T} V_\mathrm{T} + C_\mathrm{R} V_\mathrm{R}}\right)
\end{equation}
-\subsection{Pump CMDS-probe} % -------------------------------------------------------------------
-
\clearpage
\section{Instrumentation} % ======================================================================
+In this section I introduce the key components of the MR-CMDS instrument. %
\subsection{LASER} % -----------------------------------------------------------------------------
@@ -333,73 +347,3 @@ expression for $\Delta A$ that only depends on my eight measurables. % \subsection{Delay stages} % ----------------------------------------------------------------------
\subsection{Spectrometers} % ---------------------------------------------------------------------
-
-\subsection{Instrumental response function} % ----------------------------------------------------
-
-The instrumental response function (IRF) is a classic concept in analytical science. %
-Defining IRF becomes complex with instruments as complex as these, but it is still useful to
-attempt. %
-
-It is particularly useful to define bandwidth.
-
-\subsubsection{Time Domain}
-
-I will use four wave mixing to extract the time-domain pulse-width. %
-I use a driven signal \textit{e.g.} near infrared carbon tetrachloride response. %
-I'll homodyne-detect the output. %
-In my experiment I'm moving pulse 1 against pulses 2 and 3 (which are coincident). %
-
-The driven polarization, $P$, goes as the product of my input pulse \textit{intensities}:
-
-\begin{equation}
-P(T) = I_1(t-T) \times I_2(t) \times I_3(t)
-\end{equation}
-
-In our experiment we are convolving $I_1$ with $I_2 \times I_3$. %
-Each pulse has an \textit{intensity-level} width, $\sigma_1$, $\sigma_2$, and $\sigma_3$. $I_2
-\times I_3$ is itself a Gaussian, and
-\begin{eqnarray}
-\sigma_{I_2I_3} &=& \dots \\
-&=& \sqrt{\frac{\sigma_2^2\sigma_3^2}{\sigma_2^2 + \sigma_3^2}}.
-\end{eqnarray}
-
-The width of the polarization (across $T$) is therefore
-
-\begin{eqnarray}
-\sigma_P &=& \sqrt{\sigma_1^2 + \sigma_{I_2I_3}^2} \\
-&=& \dots \\
-&=& \sqrt{\frac{\sigma_1^2 + \sigma_2^2\sigma_3^2}{\sigma_1^2 + \sigma_2^2}}. \label{eq:generic}
-\end{eqnarray}
-
-% TODO: determine effect of intensity-level measurement here
-
-I assume that all of the pulses have the same width. %
-$I_1$, $I_2$, and $I_3$ are identical Gaussian functions with FWHM $\sigma$. In this case,
-\autoref{eq:generic} simplifies to
-
-\begin{eqnarray}
-\sigma_P &=& \sqrt{\frac{\sigma^2 + \sigma^2\sigma^2}{\sigma^2 + \sigma^2}} \\
-&=& \dots \\
-&=& \sigma \sqrt{\frac{3}{2}}
-\end{eqnarray}
-
-Finally, since we measure $\sigma_P$ and wish to extract $\sigma$:
-
-\begin{equation}
-\sigma = \sigma_P \sqrt{\frac{2}{3}}
-\end{equation}
-
-Again, all of these widths are on the \textit{intensity} level.
-
-\subsubsection{Frequency Domain}
-
-We can directly measure $\sigma$ (the width on the intensity-level) in the frequency domain using a
-spectrometer. %
-A tune test contains this information. %
-
-\subsubsection{Time-Bandwidth Product}
-
-For a Gaussian, approximately 0.441
-
-% TODO: find reference
-% TODO: number defined on INTENSITY level!
\ No newline at end of file |