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arXiv · 2301.11973

Gain-switched vcsel as a quantum entropy source: the problem of quantum and classical noise

Roman Shakhovoy·Elizaveta Maksimova
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Abstract

We consider the problem of quantum noise extraction from polarization swapping in a gain-switched VCSEL. The principle of operation of a quantum random number generator is based on the generation of laser pulses with one of two orthogonal polarization states, followed by digitization of polarization-resolved pulses with a comparator. At intensity values of laser pulses close to the threshold value of the comparator, the contribution of the classical noise of the photodetector will have a crucial role in making a decision on the choice of a logical zero or one. We show how to evaluate the contribution of classical noise and how to calculate the quantum reduction factor required for post-processing.

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Roman Shakhovoy, Elizaveta Maksimova. 2023-01-27. Gain-switched vcsel as a quantum entropy source: the problem of quantum and classical noise. https://doi.org/10.18721/jpm.153.237

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