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arXiv · 1908.02342

Quantum dynamics of single-photon detection using functionalized quantum transport electronic channels

Catalin D. Spataru·François Léonard
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Abstract

Single photon detectors have historically consisted of macroscopic-sized materials but recent experimental and theoretical progress suggests new approaches based on nanoscale and molecular electronics. Here we present a theoretical study of photodetection in a system composed of a quantum electronic transport channel functionalized by a photon absorber. Notably, the photon field, absorption process, transduction mechanism, and measurement process are all treated as part of one fully-coupled quantum system, with explicit interactions. Using non-equilibrium, time-dependent quantum transport simulations, we reveal the unique temporal signatures of the single photon detection process, and show that the system can be described using optical Bloch equations, with a new non-linearity as a consequence of time-dependent detuning caused by the backaction from the transport channel via the dynamical Stark effect. We compute the photodetector signal-to-noise ratio and demonstrate that single photon detection at high count rate is possible for realistic parameters by exploiting a novel non-equilibrium control of backaction.

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Catalin D. Spataru, François Léonard. 2019-08-06. Quantum dynamics of single-photon detection using functionalized quantum transport electronic channels. https://doi.org/10.1103/physrevresearch.1.013018

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