Waveguide-coupled superconducting nanowire single-photon detectors based on femtosecond laser direct writing

• Published in: Optics express Vol. 29; no. 5; pp. 7746 - 7756
• Main Authors: Hou, Xintong, Xu, Xiao-Yun, Xu, Guangzhao, You, Lixing, Jin, Xian-Min, Li, Hao, Zhang, Weijun, Ren, Ruo-Jing, Huang, Xuan-Lun, Wang, Zhen
• Format: Journal Article
• Language: English
• Published: United States 01.03.2021
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/oe.419724

The implementation of quantum information technologies requires the development of integrated quantum chips. Femtosecond laser direct writing (FLDW) waveguides and superconducting nanowire single-photon detectors (SNSPDs) have been widely applied in integrated quantum photonic circuits. In this work, a novel FLDW waveguide-coupled SNSPD was designed and realized by integrating FLDW waveguides and conventional SNSPDs together. Through a COMSOL simulation, a waveguide end face-nanowire optical coupling structure was designed and verified. The simulation results showed that the FLDW waveguide-coupled SNSPD device, which had a target wavelength of 780 nm, can achieve 87% optical absorption. Then the preparation process of the FLDW waveguide-coupled SNSPD device was developed, and the fabricated device achieved a system detection efficiency of 1.7% at 10 Hz dark count rate. Overall, this method provides a feasible single-photon detector solution for future on-chip integrated quantum photonic experiments and applications.