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arXiv · 1407.0933

Robust random number generation using steady-state emission of gain-switched laser diodes

Z. L. Yuan·M. Lucamarini·J. F. Dynes·B. Frohlich·A. Plews·A. J. Shields
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Abstract

We demonstrate robust, high-speed random number generation using interference of the steady-state emission of guaranteed random phases, obtained through gain-switching a semiconductor laser diode. Steady-state emission tolerates large temporal pulse misalignments and therefore significantly improves the interference quality. Using an 8-bit digitizer followed by a finite-impulse response unbiasing algorithm, we achieve random number generation rates of 8 and 20 Gb/s, for laser repetition rates of 1 and 2.5 GHz, respectively, with a +/-20% tolerance in the interferometer differential delay. We also report a generation rate of 80 Gb/s using partially phase-correlated short pulses. In relation to the field of quantum key distribution, our results confirm the gain-switched laser diode as a suitable light source, capable of providing phase-randomized coherent pulses at a clock rate of up to 2.5 GHz.

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Z. L. Yuan, M. Lucamarini, J. F. Dynes, B. Frohlich, A. Plews, A. J. Shields. 2014-07-03. Robust random number generation using steady-state emission of gain-switched laser diodes. https://doi.org/10.1063/1.4886761

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