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-rw-r--r--OPA_interferometry.wt5bin0 -> 800 bytes
-rw-r--r--PEDOT_PSS/chapter.tex1
-rw-r--r--dissertation.tex2
-rw-r--r--irf/chapter.tex7
-rw-r--r--opa_phase/chapter.tex64
-rw-r--r--opa_phase/darien_playing.py3
-rw-r--r--procedures/chapter.tex49
-rw-r--r--quantitative_ta/chapter.tex33
8 files changed, 86 insertions, 73 deletions
diff --git a/OPA_interferometry.wt5 b/OPA_interferometry.wt5
new file mode 100644
index 0000000..82daee0
--- /dev/null
+++ b/OPA_interferometry.wt5
Binary files differ
diff --git a/PEDOT_PSS/chapter.tex b/PEDOT_PSS/chapter.tex
index b7fba1f..10a7472 100644
--- a/PEDOT_PSS/chapter.tex
+++ b/PEDOT_PSS/chapter.tex
@@ -1,6 +1,5 @@
\chapter{PEDOT:PSS} \label{cha:pps}
-
\textit{This Chapter presents content first published in \textcite{HorakErikH2018a}.
The authors are:
\begin{denumerate}
diff --git a/dissertation.tex b/dissertation.tex
index 9c0d90a..9d40288 100644
--- a/dissertation.tex
+++ b/dissertation.tex
@@ -90,7 +90,7 @@ This dissertation is approved by the following members of the Final Oral Committ
\begin{appendix}
% AFTER DEFENSE \include{public/chapter}
\include{procedures/chapter} % prc
-\include{hardware/chapter} % hdw
+% AFTER DEFENSE \include{hardware/chapter} % hdw
\include{irf/chapter} % irf
\include{quantitative_ta/chapter} % qta
\include{opa_phase/chapter} % rpa
diff --git a/irf/chapter.tex b/irf/chapter.tex
index 07cd561..3066d9e 100644
--- a/irf/chapter.tex
+++ b/irf/chapter.tex
@@ -4,7 +4,7 @@ The instrumental response function (IRF) is a classic concept in analytical scie
Defining IRF becomes complex with instruments as complex as these, but it is still useful to
attempt. %
-It is particularly useful to define bandwidth.
+It is particularly useful to define bandwidth. %
\subsubsection{Time Domain}
@@ -63,7 +63,4 @@ 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
+For a Gaussian, approximately 0.441 \ No newline at end of file
diff --git a/opa_phase/chapter.tex b/opa_phase/chapter.tex
index 774ab45..ae1a9ea 100644
--- a/opa_phase/chapter.tex
+++ b/opa_phase/chapter.tex
@@ -1,35 +1,53 @@
\chapter{Abandon the random phase approximation} \label{cha:rpa}
-Recently we've made some measurements that seem to imply phase stability between the fs OPAs. %
-We've typically assumed that the OPAs have random phase on every shot, making coherent heterodyne
-processes average to zero. %
-These measurements show that this is a very bad assumption. %
-
-I've taken the interferogram of OPA1 vs OPA2, Clearly the OPAs remain phase locked for many shots. %
-In 'over time' I show the spectral phase pattern (D = 500 fs) for 1000 single shot acquisitions
-over 430 seconds in lab time. %
-The phase does drift, but it is certainly not quickly randomized. %
+\clearpage
+
+Historically, we've assumed that OPAs have random phase on every shot. %
+This makes interference processes quickly average to zero over many shots---we rarely take fewer
+than 100 shots per pixel. %
+Here I demonstrate that this assumption is very poor, at least for the femtosecond OPAs. %
+
+In these experiments, I simply send OPA1 and OPA2 simultaniously into the array detector. %
+The crucial detail is that the beams are exactly collinear---overlaped in a beamsplitter. %
+I then scan delay between them while collecting single shot spectra using the array detector. %
-I have more data showing:
-How the spectral phase changes over the course of hours.
-How the phase evolves as we scan the OPAs against each-other in color.
-The reproducibility of phase as the OPA motors move away and then return to a given color.
+\autoref{rpa:fig:delay} shows the results of these experiments for OPA2 vs itself
+(``auto-interference'') and vs OPA1 (``cross interference''). %
+At zero delay all colors arise simultaniously, so there are no modulations along the array axis
+(vertical). %
+As I scan further from zero modulations set in as each wavelength within the pulse has a different
+period in delay space. %
+It is crucial to remember that the monochromator acts like a stretcher, so we see interference
+between the two pulses even when separated by 400 fs. %
+
+The fringe pattern is expected in the case of auto-interference, but it is also quite stable in
+cross-interference. In the next experiment, I explore just how stable the cross-phase is.
+
+\autoref{rpa:fig:time} shows the same single-shot spectrum taken 1000 times at a fixed delay of 500
+fs. %
+The phase does drift, but it is certainly not quickly randomized. %
+In fact, the period shifts by 180 degrees in roughly one minute---much much longer than any single
+pixel that we have taken. %
-I'll work this data up and send out another email with many more details and thoughts once I have
-time. %
-This quick note is just to let the group know that we must abandon the 'random phase' assumption
-when thinking about what heterodyne processes can happen as coherent artifacts. %
+This result forces us to reconsider our assumptions when identifying potential sources of artifact
+in our measurements. %
\begin{figure}
- \includegraphics[width=\textwidth]{"opa_phase/cross interference"}
- \caption[CAPTION TODO]{
- CAPTION TODO
+ \includegraphics[width=\textwidth]{"opa_phase/auto_cross_interference"}
+ \caption[Auto-interference vs cross-interference.]{
+ Interference between OPA outputs as function of relative arrival time.
+ In the left hand plot, OPA2 interferes with itself.
+ In the right hand plot, OPA1 interferes with OPA2.
+ Signal is intensity level.
}
+ \label{rpa:fig:delay}
\end{figure}
\begin{figure}
- \includegraphics[width=\textwidth]{"opa_phase/430 seconds"}
- \caption[CAPTION TODO]{
- CAPTION TODO
+ \includegraphics[width=\textwidth]{"opa_phase/time_interference"}
+ \caption[Cross interference over 100 seconds.]{
+ Cross interference at fixed delay of 500 fs.
+ 1000 single-shot acquisitions over a period of 100 seconds in lab time.
}
+ \label{rpa:fig:time}
\end{figure}
diff --git a/opa_phase/darien_playing.py b/opa_phase/darien_playing.py
index cc8ce39..b8bd5b7 100644
--- a/opa_phase/darien_playing.py
+++ b/opa_phase/darien_playing.py
@@ -93,8 +93,7 @@ if True:
ax.set_xlabel('lab time (s)')
ax.set_ylabel(col.auto.wa.label)
ax.grid()
-
- #d.array.clip(.3)
+ d.array.clip(.3)
fig, gs = wt.artists.create_figure(width='double', cols=[1, 'cbar'], default_aspect=.5)
# overtime
ax = plt.subplot(gs[0,0])
diff --git a/procedures/chapter.tex b/procedures/chapter.tex
index fd04bc3..8c8d0b2 100644
--- a/procedures/chapter.tex
+++ b/procedures/chapter.tex
@@ -1,7 +1,17 @@
\chapter{Procedures}
-\clearpage
-\section{``Six-month'' maintenance} % ------------------------------------------------------------
+\begin{dquote}
+ These are the vegetables we must eat before we can have our pixels of ice cream.
+
+ \dsignature{Wright Group saying}.
+\end{dquote}
+
+\vfill
+
+In this chapter I document the various procedures that I have performed to maintain the MR-CMDS
+instruments. %
+
+\section{``Six-month'' maintenance} % ============================================================
The laser system that the Wright Group's MR-CMDS instruments use requires regular maintenance. %
Each component is sensitive to lab conditions such as temperature, humidity, and vibrations. %
@@ -13,7 +23,6 @@ Historically, the Wright Group has engaged in reactive maintenance: a ``fix it i
don't touch otherwise'' kind of approach. %
This approach makes a lot of sense for instruments that are quick to fix, and have few active
users. %
-
I instituted a proactive, regular maintenance procedure (described below) that has improved the
predictability of instrumental performance. %
Predictability is key for instruments with multiple users. %
@@ -48,9 +57,9 @@ Procedure:
\end{denumerate}
\item Chiller maintenance.
\begin{ditemize}
- \item See x
- \item See y
- \item See z
+ \item See \autoref{prc:sec:lytron}
+ \item See \autoref{prc:sec:polyscience}
+ \item See \autoref{prc:sec:neslab}
\end{ditemize}
\item Lab cleaning.
\begin{denumerate}
@@ -68,13 +77,9 @@ Procedure:
\end{ditemize}
\item Let lab sit overnight to allow dust to settle and the air to dehumidify.
\item Start up system again.
- \begin{denumerate}
- \item TODO
- \end{denumerate}
\end{denumerate}
-\clearpage
-\section{Lytron Kodiak RC006} % ------------------------------------------------------------------
+\section{Lytron Kodiak RC006} \label{prc:sec:lytron} % ===========================================
We have one Lytron Kodiak RC006: Model Number RC006G03BB1C002, Serial Number 739383-02.
@@ -107,10 +112,7 @@ These seem to have been fixed by adding a “high” flow loop connecting the ou
chiller. %
Ideally the pressure drop across this loop is sufficient to still drive fluid through the laser. %
-% TODO: figure
-
-\clearpage
-\section{PolyScience 6000 Series} % --------------------------------------------------------------
+\section{PolyScience 6000 Series} \label{prc:sec:polyscience} % ==================================
We own two PolyScience chillers---different models but functionally equivalent.
@@ -142,8 +144,7 @@ Regular chiller maintenance:
\end{denumerate}
\end{denumerate}
-\clearpage
-\section{NesLab Merlin M33} % ====================================================================
+\section{NesLab Merlin M33} \label{prc:sec:neslab} % =============================================
We have one NesLab Merlin M33 Chiller, Serial Number 106227049. %
@@ -171,7 +172,6 @@ Regular chiller maintenance
% TODO: figures
-\clearpage
\section{Calibrating the 407A} % =================================================================
Calibrating the 407.A
@@ -180,11 +180,11 @@ You may sometimes notice that the zero position changes dramatically from sensit
sensitivity with the 407A. If this happens, iterate through the following until zero stays
consistent:
-Use the fine adjust (knob on side) to zero the 407A on the highest sensitivity
-
-Use the front adjust (flathead screwdriver needed) to zero on the lowest sensitivity
-
-\clearpage
+\begin{ditemize}
+ \item Use the fine adjust (knob on side) to zero the 407A on the highest sensitivity.
+ \item Use the front adjust (flathead screwdriver needed) to zero on the lowest sensitivity.
+\end{ditemize}
+
\section{Millenia} % =============================================================================
\subsection{Startup} % ---------------------------------------------------------------------------
@@ -228,7 +228,6 @@ These allow us to record things like Diode hours. %
Service mode can be buggy, so it's best to leave the Millenia in normal Power mode during regular
operation. %
-\clearpage
\section{Spitfire Pro} % =========================================================================
Only tune up the Spitfire if you need to, and do not treat it casually---set aside an entire
@@ -429,7 +428,6 @@ Since we have not messed with the stretcher frequently this guide cannot be trus
square mirrors preceding the compressor.
\end{denumerate}
-\clearpage
\section{TOPAS-C} % ==============================================================================
% TODO: figure
@@ -668,7 +666,6 @@ Input poynting is adjusted to ensure good alignment through L1 and L2 into D1.
\item Measure and record power---should be over 600 mW.
\end{denumerate}
-\clearpage
\section{MicroHR Monochromator} % ================================================================
Visible Grating. %
diff --git a/quantitative_ta/chapter.tex b/quantitative_ta/chapter.tex
index c8b594d..099b606 100644
--- a/quantitative_ta/chapter.tex
+++ b/quantitative_ta/chapter.tex
@@ -1,32 +1,35 @@
-\chapter{Quantitative transient absorbance} \label{cha:qta}
+\chapter{Quantitative differential absorbance} \label{cha:qta}
-\subsubsection{Quantitative TA}
+\clearpage
Transient absorbance (TA) spectroscopy is a self-heterodyned technique. %
Through chopping you can measure nonlinearities quantitatively much easier than with homodyne
-detected (or explicitly heterodyned) experiments.
+detected (or explicitly heterodyned) experiments. %
-\begin{figure}
- \includegraphics[width=\textwidth]{"spectroscopy/TA setup"}
- \label{fig:ta_and_tr_setup}
- \caption{CAPTION TODO}
-\end{figure}
+%\begin{figure}
+% \includegraphics[width=\textwidth]{"spectroscopy/TA setup"}
+% \label{fig:ta_and_tr_setup}
+% \caption{CAPTION TODO}
+%\end{figure}
-\autoref{fig:ta_and_tr_setup} diagrams the TA measurement for a generic sample. %
-Here I show measurement of both the reflected and transmitted probe beam \dots not important in
-opaque (pyrite) or non-reflective (quantum dot) samples \dots %
+%\autoref{fig:ta_and_tr_setup} diagrams the TA measurement for a generic sample. %
+%Here I show measurement of both the reflected and transmitted probe beam \dots not important in
+%opaque (pyrite) or non-reflective (quantum dot) samples \dots %
Typically one attempts to calculate the change in absorbance $\Delta A$ \dots %
\begin{eqnarray}
\Delta A &=& A_{\mathrm{on}} - A_{\mathrm{off}} \\
-&=& -\log_{10}\left(\frac{I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}} + I_{\Delta\mathrm{R}}}{I_0}\right) + \log\left(\frac{I_\mathrm{T}+I_\mathrm{R}}{I_0}\right) \\
-&=& -\left(\log_{10}(I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}}+ I_{\Delta\mathrm{R}})-\log_{10}(I_0)\right)+\left(\log_{10}(I_\mathrm{T}+I_\mathrm{R})-\log_{10}(I_0)\right) \\
+&=& -\log_{10}\left(\frac{I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}} +
+ I_{\Delta\mathrm{R}}}{I_0}\right) + \log\left(\frac{I_\mathrm{T}+I_\mathrm{R}}{I_0}\right) \\
+&=& -\left(\log_{10}(I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}}+
+ I_{\Delta\mathrm{R}})-\log_{10}(I_0)\right)+\left(\log_{10}(I_\mathrm{T}+I_\mathrm{R})-\log_{10}(I_0)\right)
+ \\
&=& -\left(\log_{10}(I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}}+ I_{\Delta\mathrm{R}})-\log_{10}(I_\mathrm{T}+I_\mathrm{R})\right) \\
-&=& -\log_{10}\left(\frac{I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}}+ I_{\Delta\mathrm{R}}}{I_\mathrm{T}+I_\mathrm{R}}\right) \label{eq:ta_complete}
+&=& -\log_{10}\left(\frac{I_\mathrm{T}+I_\mathrm{R}+I_{\Delta\mathrm{T}}+ I_{\Delta\mathrm{R}}}{I_\mathrm{T}+I_\mathrm{R}}\right) \label{qta:eqn:ta_complete}
\end{eqnarray}
-\autoref{eq:ta_complete} simplifies beautifully if reflectivity is negligible \dots
+\autoref{qta:eqn:ta_complete} simplifies beautifully if reflectivity is negligible \dots
Now I define a variable for each experimental measurable:
\begin{center}