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arXiv:2411.09494 · Physical Review Applied

Laser-induced relaxation oscillations in superconducting nanobridge single-photon detectors

F. B. Baalbergen, Iman Esmaeil Zadeh, M. J. A. de Dood

Published May 27, 2025• 1 citation
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Abstract

We demonstrate laser-induced relaxation oscillations in superconducting nanowire single-photon detectors (SNSPDs). These oscillations appear when a voltage-biased Nb Ti N nanobridge detector is illuminated with intense pulsed-laser light at a repetition rate of approximately 19 MHz . They differ from the well-known relaxation oscillations by a stepwise increase in frequency and phase locking of the oscillations to the laser pulses. We create a model that incorporates electrical feedback and excludes thermal effects to simulate and explain the origin of the observed laser-induced relaxation oscillations. Qualitative agreement to the experiment is achieved using realistic values for the parameters in the model.

DOI
10.1103/cxv8-fqy9

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