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Entry  Thu Apr 1 00:43:33 2010, Mott, Update, General, PZT response for the innolight Innolight_Bode.png
    Reply  Thu Apr 1 07:17:15 2010, Koji, Update, General, PZT response for the innolight 
       Reply  Thu Apr 1 10:21:58 2010, Mott, Update, General, PZT response for the innolight Innolight_Response.pngLightwave_response.png
          Reply  Thu Apr 1 10:47:48 2010, Koji, Update, General, PZT response for the innolight 
             Reply  Thu Apr 1 12:07:22 2010, rana, Update, General, PZT response for the innolight 
                Reply  Thu Apr 1 18:05:29 2010, Mott, Update, General, PZT response for the innolight Innolight_Response_calFix.pngLightwave_response_calFix.png
                   Reply  Thu Apr 1 18:44:40 2010, Koji, Update, General, PZT response for the innolight 
                      Reply  Thu Apr 1 19:59:32 2010, Mott, Update, General, PZT response for the innolight Innolight_AM_Response.pngInnolight_AM_PM.pngInnoVsLW_PM.pngInnolight_AM_Response.pngLightwave_AM_PM.png
                         Reply  Mon Apr 12 14:20:10 2010, kiwamu, Update, Green Locking, PZT response for the innolight 
                            Reply  Tue Apr 13 19:53:06 2010, Mott, Update, Green Locking, PZT response for the innolight and lightwave 6x
Message ID: 2799     Entry time: Tue Apr 13 19:53:06 2010     In reply to: 2788
Author: Mott 
Type: Update 
Category: Green Locking 
Subject: PZT response for the innolight and lightwave 

 

 I redid the PZT Phase Modulation measurement out to 5 MHz for both the Innolight and the Lightwave.  The previous measurement stopped at 2MHz, and we wanted to see if there were any sweet spots above 2MHz.  I also reduced the sweep bandwidth and increased the source amplitude at high frequency to reduce the noise (the Lighwave measurement, especially, was noise dominated above 1MHz).  I also plotted the ratio of PM/AM in rad/RIN, since this is the ultimate criterion on which we want to make a determination.

It looks like there is nothing extremely useful above 2MHz for either laser.  There are several candidates for the lightwave at about 140 kHz and again at about 1.4 MHz.  The most compelling peak, however, is in the innolight at 216 kHz, where the peak is about 2.3e5 rad/RIN.

Below about 30kHz, the loop suppresses the measurement, so one should focus on the region above there.

Attachment 1: Innolight_PM.png  29 kB  | Hide | Hide all
Innolight_PM.png
Attachment 2: Innolight_AM_PM.png  53 kB  | Hide | Hide all
Innolight_AM_PM.png
Attachment 3: Innolight_PM_AM_Ratio.png  48 kB  | Hide | Hide all
Innolight_PM_AM_Ratio.png
Attachment 4: Lightwave_PM.png  30 kB  | Hide | Hide all
Lightwave_PM.png
Attachment 5: Lightwave_AM_PM.png  53 kB  | Hide | Hide all
Lightwave_AM_PM.png
Attachment 6: Lightwave_PM_AM_Ratio.png  50 kB  | Hide | Hide all
Lightwave_PM_AM_Ratio.png
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