title: Design of a polarization-insensitive superconducting nanowire single photon detector with high detection efficiency.
abstract: Superconducting nanowire single photon detectors (SNSPDs) deliver superior performance over their competitors in the near-infrared regime. However, these detectors have an intrinsic polarization dependence on the incident wave because of their one-dimensional meander structure. In this paper, we propose an approach to eliminate the polarization sensitivity of SNSPDs by using near-field optics to increase the absorption of SNSPDs under transverse magnetic (TM) illumination. In addition, an optical cavity is added to our SNSPD to obtain nearly perfect absorption of the incident wave. Numerical simulations show that the maximum absorption of a designed SNSPD can reach 96% at 1550 nm, and indicate that the absorption difference between transverse electric (TE) and TM polarization is less than 0.5% across a wavelength window of 300 nm. Our work provides the first demonstration of the possibility of designing a polarization-insensitive and highly efficient SNSPD without performing device symmetry improvements.
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Fan
authors.initials: F
authors.lastname: Zheng
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Ruiying
authors.initials: R
authors.lastname: Xu
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Guanghao
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Biaobing
authors.initials: B
authors.lastname: Jin
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Lin
authors.initials: L
authors.lastname: Kang
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Xu
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.affiliation: Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing, China 210023.
authors.forename: Peiheng
authors.initials: P
authors.lastname: Wu