From 357568e1fb77afed9dfa203e62da237bf7ce51b3 Mon Sep 17 00:00:00 2001 From: Blaise Thompson Date: Mon, 9 Apr 2018 00:24:18 -0500 Subject: 2018-04-09 00:24 --- opa_phase/430 seconds.png | Bin 0 -> 220783 bytes opa_phase/chapter.tex | 35 +++++++++++++++++++++++++++++++++++ opa_phase/cross interference.png | Bin 0 -> 180297 bytes 3 files changed, 35 insertions(+) create mode 100644 opa_phase/430 seconds.png create mode 100644 opa_phase/chapter.tex create mode 100644 opa_phase/cross interference.png (limited to 'opa_phase') diff --git a/opa_phase/430 seconds.png b/opa_phase/430 seconds.png new file mode 100644 index 0000000..e9c5cf5 Binary files /dev/null and b/opa_phase/430 seconds.png differ diff --git a/opa_phase/chapter.tex b/opa_phase/chapter.tex new file mode 100644 index 0000000..774ab45 --- /dev/null +++ b/opa_phase/chapter.tex @@ -0,0 +1,35 @@ +\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. % + +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. + +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. % + +\begin{figure} + \includegraphics[width=\textwidth]{"opa_phase/cross interference"} + \caption[CAPTION TODO]{ + CAPTION TODO + } +\end{figure} + +\begin{figure} + \includegraphics[width=\textwidth]{"opa_phase/430 seconds"} + \caption[CAPTION TODO]{ + CAPTION TODO + } +\end{figure} diff --git a/opa_phase/cross interference.png b/opa_phase/cross interference.png new file mode 100644 index 0000000..8891214 Binary files /dev/null and b/opa_phase/cross interference.png differ -- cgit v1.2.3