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arXiv · 2410.03715

Dynamical spectra from one and two-photon Fock state pulses exciting a single chiral qubit in a waveguide

Sofia Arranz Regidor·Andreas Knorr·Stephen Hughes
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Abstract

We study the dynamical light emission from few-photon Fock states in waveguide-QED with a chiral two-level system. We first investigate the time dynamics of the system by calculating the emitter population and illustrate the breakdown of the weak excitation approximation, for both 1-photon and 2-photon excitation. We show how a 1-photon pulse yields a transmitted long-time spectrum that is identical to the input pulse, despite significant population effects. However, the dynamical spectra and spectral intensity show rich population effects. We also show the differences between 1-photon and 2-photon excitation, where the latter shows clear signatures of nonlinear saturation effects. Analytical and numerically exact matrix product state solutions are shown.

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Sofia Arranz Regidor, Andreas Knorr, Stephen Hughes. 2024-09-27. Dynamical spectra from one and two-photon Fock state pulses exciting a single chiral qubit in a waveguide. https://arxiv.org/abs/2410.03715

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