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arXiv · 2403.08674

Quantum jump photodetector for narrowband photon counting with a single atom

Laura Zarraoa·Romain Veyron·Tomas Lamich·Lorena C. Bianchet·Morgan W. Mitchell
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Abstract

Using a single neutral 87Rb atom held in an optical trap, and "quantum jump" detection of single-photon-initiated state changes, we demonstrate a single-photon quantum jump photodetector (QJPD) with intrinsically narrow bandwidth and strong rejection of out-of-band photons, of interest for detecting weak optical signals in the presence of a strong broadband background. By analyzing fluorescence photon count distributions for the bright and dark states with and without excitation, we measure quantum efficiency of 2.9(2)$\times 10^{-3}$, a record for single-pass quantum jump production, and signal-photon-unprovoked "dark jump" rate - analogous to the dark count rate of other detectors - 3(10)$\times 10^{-3}$ jumps per second during passive accumulation plus 4.0(4)$\times 10^{-3}$ jumps per readout, orders of magnitude below those of traditional single-photon detectors. Available methods can substantially improve QJPD quantum efficiency, dark jump rate, bandwidth and tunability.

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Laura Zarraoa, Romain Veyron, Tomas Lamich, Lorena C. Bianchet, Morgan W. Mitchell. 2024-03-13. Quantum jump photodetector for narrowband photon counting with a single atom. https://doi.org/10.1103/physrevresearch.6.033338

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