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arXiv · 1701.04709

Ultrastrong coupling few-photon scattering theory

Tao Shi·Yue Chang·Juan Jose Garcia-Ripoll
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Abstract

We study the scattering of photons by a two-level system ultrastrongly coupled to a one-dimensional waveguide. Using a combination of the polaron transformation with scattering theory we can compute the one-photon scattering properties of the qubit for a broad range of coupling strengths, estimating resonance frequencies, lineshapes and linewidths. We validate numerically and analytically the accuracy of this technique up to $\alpha=0.3$, close to the Toulouse point $\alpha=1/2$, where inelastic scattering becomes relevant. These methods model recent experiments with superconducting circuits [P. Forn-D{\'\i}az et al., Nat. Phys. (2016)].

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Tao Shi, Yue Chang, Juan Jose Garcia-Ripoll. 2017-01-17. Ultrastrong coupling few-photon scattering theory. https://doi.org/10.1103/physrevlett.120.153602

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