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arXiv · 1907.10441

Observing the Spectral Collapse of Two-Photon Interaction Models

Simone Felicetti·Alexandre Le Boité
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Abstract

Until very recently, two-photon interaction processes have been considered only as arising from second- or higher-order effects in driven systems, and so limited to extremely small coupling strengths. However, a variety of novel physical phenomena emerges in the strong and ultrastrong coupling regimes. Strikingly, for a critical value of the coupling strength the discrete spectrum collapses into a continuous band. In this extended abstract, we discuss recent proposals to implement genuine two-photon interactions in an undriven solid-state system, in the framework of circuit QED. In particular, we review counterintuitive spectral features of two-photon interaction models and we show how the onset of the spectral collapse can be observed in feasible scattering experiments.

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Simone Felicetti, Alexandre Le Boité. 2019-07-24. Observing the Spectral Collapse of Two-Photon Interaction Models. https://doi.org/10.3390/proceedings2019012041

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