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arXiv · 2103.09896

Multifunctional Superconducting Nanowire Quantum Sensors

Benjamin J Lawrie·Claire E. Marvinney·Yun-Yi Pai·Matthew A. Feldman·Jie Zhang·Aaron J. Miller·Chengyun Hua·Eugene Dumitrescu·Gábor B. Halász
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Abstract

Superconducting nanowire single photon detectors (SNSPDs) offer high-quantum-efficiency and low-dark-count-rate single photon detection. In a growing number of cases, large magnetic fields are being incorporated into quantum microscopes, nanophotonic devices, and sensors for nuclear and high-energy physics that rely on SNSPDs, but superconducting devices generally operate poorly in large magnetic fields. Here, we demonstrate robust performance of amorphous SNSPDs in magnetic fields of up to $\pm 6$ T with a negligible dark count rate and unchanged quantum efficiency at typical bias currents. Critically, we also show that in the electrothermal oscillation regime, the SNSPD can be used as a magnetometer with sensitivity of better than 100 $\mathrm{\mu T/\sqrt{Hz}}$ and as a thermometer with sensitivity of 20 $\mathrm{\mu K/\sqrt{Hz}}$ at 1 K. Thus, a single photon detector integrated into a quantum device can be used as a multifunctional quantum sensor capable of describing the temperature and magnetic field on-chip simply by varying the bias current to change the operating modality from single photon detection to thermometry or magnetometry.

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Benjamin J Lawrie, Claire E. Marvinney, Yun-Yi Pai, Matthew A. Feldman, Jie Zhang, Aaron J. Miller, Chengyun Hua, Eugene Dumitrescu, Gábor B. Halász. 2021-03-17. Multifunctional Superconducting Nanowire Quantum Sensors. https://doi.org/10.1103/physrevapplied.16.064059

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