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arXiv · 1402.2879

Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector

Robert M. Heath·Michael G. Tanner·Alessandro Casaburi·Mark G. Webster·Lara San Emeterio Alvarez·Zoe H. Barber·Richard J. Warburton·Robert H. Hadfield
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Abstract

The device physics of parallel-wire superconducting nanowire single photon detectors is based on a cascade process. Using nano-optical techniques and a parallel wire device with spatially-separate pixels we explicitly demonstrate the single- and multi-photon triggering regimes. We develop a model for describing efficiency of a detector operating in the arm-trigger regime. We investigate the timing response of the detector when illuminating a single pixel and two pixels. We see a change in the active area of the detector between the two regimes and find the two-pixel trigger regime to have a faster timing response than the one-pixel regime.

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Robert M. Heath, Michael G. Tanner, Alessandro Casaburi, Mark G. Webster, Lara San Emeterio Alvarez, Zoe H. Barber, Richard J. Warburton, Robert H. Hadfield. 2014-02-12. Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector. https://doi.org/10.1063/1.4865199

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