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arXiv · 2411.09494

Laser-Induced Relaxation Oscillations in Superconducting Nanobridge Single Photon Detectors

F. B. Baalbergen·I. E. Zadeh·M. J. A. de Dood
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Abstract

We demonstrate novel laser-induced relaxation oscillations in superconducting nanowire single photon detectors (SNSPDs). These oscillations appear when a voltage biased NbTiN nanobridge detector is illuminated with intense pulsed laser light at a repetition rate of $\sim19\text{MHz}$. They differ from the well-known relaxation oscillations by a step-wise 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.

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F. B. Baalbergen, I. E. Zadeh, M. J. A. de Dood. 2024-11-14. Laser-Induced Relaxation Oscillations in Superconducting Nanobridge Single Photon Detectors. https://doi.org/10.1103/cxv8-fqy9

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