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.
@article{arxiv.1907.10441,
title = {Observing the Spectral Collapse of Two-Photon Interaction Models},
author = {Simone Felicetti and Alexandre Le Boité},
journal= {arXiv preprint arXiv:1907.10441},
year = {2019}
}
Comments
Presented at the 11th Italian Quantum Information Science Conference (IQIS2018), Catania, Italy, 17-20 September 2018