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arXiv · 2210.15215

Single photon detection performance of highly disordered NbTiN thin films

Ruoyan Ma·Rui Shu·Xingyu Zhang·Aobo Yu·Huang Jia·You Xiao·Huiqin Yu·Xiaoyu Liu·Hao Li·Per Eklund·Xiaofu Zhang·Lixing You
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Abstract

We experimentally investigated the detection performance of highly disordered NbxTi1-xN based superconducting nanowire single photon detectors (SNSPDs). The dependence on the composition of the transition temperature Tc for NbxTi1-xN films show a dome-like behavior on the Nb content, with a maximal Tc at xNb~0.65 , and the Nb0.65Ti0.35N films also combine relatively large sheet resistance and intermediate residual resistivity ratio. Moreover, 60-nm-wide and 7-nm-thick Nb0.65Ti0.35N nanowires show a switching current as high as 14.5 uA, and saturated intrinsic detection efficiency with a plateau of more than 2 uA at 2.4 K. Finally, the corresponding SNSPDs on an alternative SiO2/Ta2O5 dielectric mirror showed a system detection efficiency of approximately 92% for 1550 nm photons, and the timing jitter is around 26 ps. Our results demonstrate that the highly disordered NbxTi1-xN films are promising for fabricating SNSPDs for near- and middle-infrared single photons with high detection efficiency and low timing jitter.

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Ruoyan Ma, Rui Shu, Xingyu Zhang, Aobo Yu, Huang Jia, You Xiao, Huiqin Yu, Xiaoyu Liu, Hao Li, Per Eklund, Xiaofu Zhang, Lixing You. 2022-10-27. Single photon detection performance of highly disordered NbTiN thin films. https://arxiv.org/abs/2210.15215

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