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 ±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 μT/Hz and as a thermometer with sensitivity of 20 μK/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.
@article{arxiv.2103.09896,
title = {Multifunctional Superconducting Nanowire Quantum Sensors},
author = {Benjamin J Lawrie and Claire E. Marvinney and Yun-Yi Pai and Matthew A. Feldman and Jie Zhang and Aaron J. Miller and Chengyun Hua and Eugene Dumitrescu and Gábor B. Halász},
journal= {arXiv preprint arXiv:2103.09896},
year = {2021}
}