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Broadband low-noise photodetector for Pound-Drever-Hall laser stabilization

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 نشر من قبل Amar Vutha
 تاريخ النشر 2016
  مجال البحث فيزياء
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The Pound-Drever-Hall laser stabilization technique requires a fast, low-noise photodetector. We present a simple photodetector design that uses a transformer as an intermediary between a photodiode and cascaded low-noise radio-frequency amplifiers. Our implementation using a silicon photodiode yields a detector with 50 MHz bandwidth, gain $> 10^5$ V/A, and input current noise $< 4$ pA/$sqrt{mathrm{Hz}}$, allowing us to obtain shot-noise-limited performance with low optical power.



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