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arXiv · 1906.01007

Quantum jump statistics with a shifted jump operator in a chiral waveguide

Dario Cilluffo·Salvatore Lorenzo·G. Massimo Palma·Francesco Ciccarello
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Abstract

Resonance fluorescence, consisting of light emission from an atom driven by a classical oscillating field, is well-known to yield a sub-Poissonian photon counting statistics. This occurs when only emitted light is detected, which corresponds to a master equation (ME) unraveling in terms of the canonical jump operator describing spontaneous decay. Formally, an alternative ME unraveling is possible in terms of a shifted jump operator. We show that this shift can result in sub-Poissonian, Poissonian or super-Poissonian quantum jump statistics. This is shown in terms of the Mandel Q parameter in the limit of long counting times, which is computed through large deviation theory. We present a waveguide-QED setup, comprising a chiral waveguide coupled to a driven atom, where photon counting is described by the considered class of shifted jump operators.

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Dario Cilluffo, Salvatore Lorenzo, G. Massimo Palma, Francesco Ciccarello. 2020-01-29. Quantum jump statistics with a shifted jump operator in a chiral waveguide. https://doi.org/10.1088/1742-5468%2Fab371c

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