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arXiv · 2102.08746

Faking photon number on a transition-edge sensor

Poompong Chaiwongkhot·Jiaqiang Zhong·Anqi Huang·Hao Qin·Sheng-cai Shi·Vadim Makarov
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Abstract

We study potential security vulnerabilities of a single-photon detector based on superconducting transition-edge sensor. In a simple experiment, we show that an adversary could fake a photon number result at a certain wavelength by sending a larger number of photons at a longer wavelength. In another experiment, we show that the detector can be blinded by bright continuous-wave light and then, a controlled response simulating single-photon detection can be produced by applying a bright light pulse. We model an intercept-and-resend attack on a quantum key distribution system that exploits the latter vulnerability and, under certain assumptions, succeeds to steal the key.

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Poompong Chaiwongkhot, Jiaqiang Zhong, Anqi Huang, Hao Qin, Sheng-cai Shi, Vadim Makarov. 2021-02-17. Faking photon number on a transition-edge sensor. https://doi.org/10.1140/epjqt/s40507-022-00141-2

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