Disorder enhanced relative intrinsic detection efficiency in NbTiN superconducting nanowire single photon detectors at high temperature

Authors:
raw_author_name: Qingchang Huan
raw_affiliation_string: School of Microelectronics, Shanghai University 4 , 20 Chengzhong Road, Shanghai 201800, China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: Jia Huang
raw_affiliation_string: National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: Xingyu Zhang
raw_affiliation_string: National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: You Xiao
raw_affiliation_string: National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: Hongxing Xu
raw_affiliation_string: Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences 3 , Beijing 100049, China; National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: Hao Li
raw_affiliation_string: Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences 3 , Beijing 100049, China; National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China
raw_author_name: Lixing You
raw_affiliation_string: Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences 3 , Beijing 100049, China; National Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology 2 , Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 China; Shanghai Key Laboratory of Superconductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology 1 , 865 Changning Road, Shanghai 200050, China

Abstract: The intrinsic detection performance of superconducting nanowire single photon detectors (SNSPDs) is highly dependent on the superconducting properties of underlying thin films. This report outlines the enhancement of detection performance for single telecom wavelength photons in disordered NbTiN SNSPD at 4.2 K. By increasing the nitrogen content and deposition pressure, the NbTiN films show suppression in critical temperature and an increase in sheet resistance. Notably, the resulting SNSPDs display a broader saturation plateau at 2.2 K, leading to superior detection performance at 4.2 K. With the disordered 7-nm-thick NbTiN films, we fabricated SNSPDs with system detection efficiency up to 83% for 1550 nm photons at 4.2 K. Moreover, these devices also show saturated intrinsic detection efficiency for 2000 nm photons. With the features outlined, the devices can be integrated into the idle 4.2 K stage of the dilution refrigerator for applications in optical quantum information processing or utilize for detecting laser radar signals in airborne platforms.