Single photon detector with high polarization sensitivity.

Qi Guo,Weijun Zhang,Xiaoming Xie,Lixing You,Lu Zhang,Ming Qi,Hao Li,Zhen Wang

doi:10.1038/srep09616

Abstract

Polarization is one of the key parameters of light. Most optical detectors are intensity detectors that are insensitive to the polarization of light. A superconducting nanowire single photon detector (SNSPD) is naturally sensitive to polarization due to its nanowire structure. Previous studies focused on producing a polarization-insensitive SNSPD. In this study, by adjusting the width and pitch of the nanowire, we systematically investigate the preparation of an SNSPD with high polarization sensitivity. Subsequently, an SNSPD with a system detection efficiency of 12% and a polarization extinction ratio of 22 was successfully prepared.

Highlights

State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, 865 Changning Rd., Shanghai 200050, China
For a transverse magnetic (TM) wave with the electrical field perpendicular to the nanowire, the magnetic field intensity is uniform across the wire; for a transverse electric (TE) wave with the magnetic field perpendicular to the nanowire, the electrical field intensity is uniform across the wire
superconducting nanowire single photon detector (SNSPD) devices were fabricated from NbN film deposited on thermal oxidized Si substrate and packaged with light illuminated from the backside of the substrate

Summary

Introduction

Most optical detectors are intensity detectors that are insensitive to the polarization of light. A superconducting nanowire single photon detector (SNSPD) is naturally sensitive to polarization due to its nanowire structure. By adjusting the width and pitch of the nanowire, we systematically investigate the preparation of an SNSPD with high polarization sensitivity. An SNSPD with a system detection efficiency of 12% and a polarization extinction ratio of 22 was successfully prepared. Most conventional optical detectors are intensity detectors, which are insensitive to the polarization of light. There are no reports on semiconducting single photon detectors (SPDs) with polarization sensitivity to the best of our knowledge. We systematically discuss the relationships between the polarization extinction ratio (PER) and SNSPD geometric parameters (width, pitch, etc.). SNSPDs with high PER are fabricated, and a detection efficiency (DE) of 12% and PER of 22 are successfully attained

Methods

Results

Conclusion