Characterizing Phase Noise in a Gain-Switched Laser Diode for Quantum Random-Number Generation

V Lovic, Davide Giacomo Marangon, Marco Lucamarini, Zhiliang Yuan, Andrew J. Shields

Research output: Contribution to journalArticlepeer-review


While operating a quantum random-number generator (QRNG), it is extremely useful to have a model of the physical entropy source to guarantee that the device is delivering randomness of genuine quantum origin. In this work we consider a QRNG based on a gain-switched laser diode and we develop a model to quantify its phase noise. This model is based on the laser rate equations and the state-of-the-art techniques for the characterization of laser diodes used in lightwave systems. These tools let us achieve a faithful modeling of the phase noise and we verify its accuracy through comparisons with experimental measurements. Furthermore, the model can be used to select optimal parameters to maximize the QRNG performance and monitor the device behavior to detect malfunctioning or malicious tampering of the device.
Original languageEnglish
Article number054012
Number of pages12
JournalPhysical Review Applied
Publication statusPublished - 4 Nov 2021

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