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arXiv · 2006.09643

Epitaxial niobium nitride superconducting nanowire single-photon detectors

Risheng Cheng·John Wright·Huili G. Xing·Debdeep Jena·Hong X. Tang
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Abstract

Superconducting nanowires used in single-photon detectors have been realized on amorphous or poly-crystalline films. Here, we report the use of single-crystalline NbN thin films for superconducting nanowire single-photon detectors (SNSPDs). Grown by molecular beam epitaxy (MBE) at high temperature on nearly lattice-matched AlN-on-sapphire substrates, the NbN films exhibit high degree of uniformity and homogeneity. Even with relatively thick films, the fabricated nanowire detectors show saturated internal efficiency at near-IR wavelengths, demonstrating the potential of MBE-grown NbN for realizing large arrays of on-chip SNSPDs and their integration with AlN-based $\chi^{(2)}$ quantum photonic circuits.

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Risheng Cheng, John Wright, Huili G. Xing, Debdeep Jena, Hong X. Tang. 2020-06-17. Epitaxial niobium nitride superconducting nanowire single-photon detectors. https://doi.org/10.1063/5.0018818

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