Title：High-speed superconducting nanowire single-photon detector (SNSPD) with strong absorption structure and preparation method of high-speed SNSPD

Country：China

Patent No.：201210333661.7

Legal Status：Authorized

Inventor：Risheng Cheng, Jianshe Liu, Tiefu Li, Wei Chen

Assignee：Tsinghua University

Address：Tsinghua University,Haidian District Beijing 100089, China

Filing Date：2012-09-10

Issue Date：2014-10-08

The invention discloses a high-speed superconducting nanowire single-photon detector (SNSPD) with a strong absorption structure and a preparation method of the high-speed SNSPD with the strong absorption structure. The SNSPD is capable of further improving the photon absorptivity of superconducting nanowires based on an incident medium with a high refractive index and an air cavity structure. Compared with the prior art and according to the high-speed SNSPD, under the condition that the nanowires are made of superconducting ultrathin membranes with the same material and the same thickness, nearly 100% of absorptivity can be realized through a lower duty ratio, and the difficulty of electron beams in the exposure steps is reduced greatly, thereby particularly being more beneficial to the preparation of the ultrathin nanowires; and meanwhile, by adopting a silicon on insulator (SOI) substrate, the high-quality growth of the superconducting ultrathin membranes can be ensured simultaneously without affecting the intrinsic quantum efficiency of the detector. In addition, under the condition that the large effective detection area is ensured equally, as the total length of the required nanowires is reduced obviously, the maximum counting rate of the detector can be improved, and the probability of occurring defects during preparation process is decreased notably.

Patent Certificate： PDF/Jpg