%!TEX root = qlight-poster2017.tex
\begin{center}
  {\bf \Large \textsf{Time resolution of TES for CW sources}}\\[.2cm]
collaborators:~Thomas Gerrits$^2$, Adriana~E.~Lita$^2$, Sae~Woo~Nam$^2$\\[-.2cm]
\end{center}
    Transition edge sensors (TES) is a high efficiency light detectors.
    For continuous wave (CW) sources with large mean photon number
    its energy resolving ability and timing accuracy is compromised by the slow recovery time on the order of microseconds.
    We
    present an approach to
    assign arrival times to overlapping detection events.
    % in the regime of low signal to noise ratio, as in the case of TES detection of near-infrared radiation.
    We use
    a two-level discriminator to coarsely locate pulses in time,
    and timestamp individual photoevents by fitting to a heuristic model.
    As an example of the application of
    We test our method
    measuring
    the second-order time correlation
    of a coherent source in a single spatial mode using a single TES detector.\\[.2cm]
\begin{figurehere}
\begin{minipage}{0.2\linewidth}
    \centering
    \includegraphics[width=1\columnwidth]{tes_pulse/TES-setup.pdf}\\[1cm]
    \includegraphics[width=1.2\columnwidth]{tes_pulse/TesSquidIntegrator.eps}
\end{minipage}
\begin{minipage}{0.8\linewidth}
    \centering
\includegraphics[width=0.48\columnwidth]{tes_pulse/2ph_fit} %\vspace*{5mm}
\includegraphics[width=0.48\columnwidth]{tes_pulse/g2_cw}
\end{minipage}
\figcaption{Top left: experimental setup: a CW laser diode centered at 810~nm
    with a variable attenuator to control the average photon number.
    Bottom right: schematics of the TES signal detection and amplification.
    Center: overlapping pulses, corresponding to two photon detection events, with fit to the heuristic model based on average single photon response.
    Right: second order autocorrelation of the laser light obtained with the TES.}
\end{figurehere}