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arXiv · 2408.15959

Mid-infrared characterization of NbTiN superconducting nanowire single-photon detectors on silicon-on-insulator

Abstract

Superconducting nanowire single-photon detectors are widely used for detecting individual photons across various wavelengths from ultraviolet to near-infrared range. Recently, there has been increasing interest in enhancing their sensitivity to single photons in the mid-infrared spectrum, driven by applications in quantum communication, spectroscopy and astrophysics. Here, we present our efforts to expand the spectral detection capabilities of U-shaped NbTiN-based superconducting nanowire single-photon detectors, fabricated in a 2-wire configuration on a silicon-on-insulator substrate, into the mid-infrared range. We demonstrate saturated internal detection efficiency extending up to a wavelength of 3.5 {\mu}m for a 5 nm thick and 50 nm wide NbTiN nanowire with a dark count rate less than 10 counts per second at 0.9 K and a rapid recovery time of 4.3 ns. The detectors are engineered for integration on waveguides in a silicon-on-insulator platform for compact, multi-channel device applications.

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Adan Azem, Dmitry V. Morozov, Daniel Kuznesof, Ciro Bruscino, Robert H. Hadfield, Lukas Chrostowski, Jeff F. Young. 2024-08-28. Mid-infrared characterization of NbTiN superconducting nanowire single-photon detectors on silicon-on-insulator. https://arxiv.org/abs/2408.15959

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