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Entry  Mon Mar 6 12:34:30 2017, johannes, Summary, ASS, ASS light injection scenarios 
    Reply  Mon Aug 21 20:11:25 2017, johannes, Summary, General, Loss measurements plan 
       Reply  Mon Aug 21 21:26:41 2017, gautam, Summary, General, Loss measurements plan 
          Reply  Tue Aug 22 16:56:54 2017, johannes, Summary, General, AS laser existing components inventory 
             Reply  Mon Aug 28 23:22:56 2017, johannes, Update, PSL, PSL table auxiliary NPRO aom_switching_zoomin.pngaom_switching_zoomout.pngaom_switching_mini_zoomin.pngaom_switching_mini_zoomout.png
                Reply  Tue Aug 29 20:04:09 2017, rana, Update, PSL, PSL table auxiliary NPRO 
                   Reply  Tue Aug 29 21:36:59 2017, johannes, Update, PSL, PSL table auxiliary NPRO isomet_mini_1st_zoomout.pngisomet_mini_0th_zoomout.png
                      Reply  Tue Sep 5 23:13:44 2017, johannes, Update, PSL, PSL table auxiliary NPRO PSL_IR.pdfpsl_aux_laser.pdf
                         Reply  Thu Sep 7 23:09:00 2017, johannes, Update, PSL, PSL table auxiliary NPRO 3200-1113_200_switching_PD10A_zoomin.png3200-1113_200_switching_PD10A_zoomout.png
                            Reply  Mon Sep 11 12:40:32 2017, johannes, Update, PSL, PSL table auxiliary NPRO psl_aux_laser2.svg.pngPSL_IR2.png
Message ID: 13270     Entry time: Tue Aug 29 20:04:09 2017     In reply to: 13264     Reply to this: 13271
Author: rana 
Type: Update 
Category: PSL 
Subject: PSL table auxiliary NPRO 

I don't understand why the 1st order diffracted beam doesn't go to zero when you shut off the drive. My guess is that the standing acoustic wave in the AO crystal needs some time to decay: f = 40 MHz, tau = 1 usec... Q ~ 100. Perhaps, the crystal is damped by the PZT and ther output impedance of the mini-circuits switch is different from the AO driver.

In any case, if you need a faster shut off, or want something that more cleanly goes to zero, there is a large (~1 cm) aperture Pockels cell that Frank Siefert was using for making pulses to damage photo diodes. There is a DEI Pulser unit near the entrance to the QIL in Bridge which can drive it.

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