Optics Letters

Fractal superconducting nanowire single-photon detectors working in dual bands and their applications in free-space and underwater hybrid LIDAR

Kai Zou, Zifan Hao, Yifan Feng, Yun Meng, Nan Hu, Stephan Steinhauer, Samuel Gyger, Val Zwiller, Xiaolong Hu

Published Dec 14, 2022• 17 citations

Abstract

We demonstrate a fiber-coupled fractal superconducting nanowire single-photon detector (SNSPD) system with minimum polarization dependence of detection efficiency. Its system detection efficiency (SDE) was maximized at the wavelength of 1540 nm, which was measured to be 91 ± 4%; furthermore, we observed the second local maximum of SDE at the wavelength of 520 nm, which was measured to be 61 ± 2%. This dual-band feature of SDE was due to the enhancement of the optical absorptance by two longitudinal resonance modes of the micro-cavity. By using high SDE with minimum polarization dependence in these two bands, we implemented a hybrid LIDAR for imaging the remote objects in free space and under water.

DOI: 10.1364/ol.481226

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