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Entry  Sat Nov 21 13:58:30 2020, Koji, Electronics, Characterization, Dark Current Measurement for InGaAs QPDs Q3000_dark_current.pdf
    Reply  Sun Nov 22 13:49:12 2020, Koji, Electronics, Characterization, Impedance Measurement for InGaAs QPDs impedance_measurement.pdfP_20201121_183830.jpgimpedance_test.pdfQ3000_impedance_test.pdf
       Reply  Mon Nov 23 23:17:19 2020, Koji, Electronics, Characterization, The dark noise of the Q3000 QPDs Q3000_dark_noise_81.pdfQ3000_dark_noise_82.pdfQ3000_dark_noise_83.pdfQ3000_dark_noise_84.pdf
          Reply  Tue Nov 24 10:45:07 2020, gautam, Electronics, Characterization, The dark noise of the Q3000 QPDs 
             Reply  Tue Nov 24 12:27:18 2020, Koji, Electronics, Characterization, The dark noise of the Q3000 QPDs 
Message ID: 405     Entry time: Tue Nov 24 10:45:07 2020     In reply to: 404     Reply to this: 406
Author: gautam 
Type: Electronics 
Category: Characterization 
Subject: The dark noise of the Q3000 QPDs 

I see that these measurements are done out to 100 kHz - I guess there is no reason to suspect anything at 55 MHz which is where this QPD will be reading out photocurrent given the low frequency behavior looks fine? The broad feature at ~80 kHz is the usual SR785 feature I guess, IIRC it's got to do with the display scanning rate.

Quote:

The measured floor level of the dark current was below the shot noise level for the DC current of 0.1mA (i.e. 6pA/rtHz).

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