- Letter
Nonperturbative effects of deep strong light-matter interaction in a mesoscopic cavity-QED system
Phys. Rev. A 108, L051701 – Published 13 November, 2023
DOI: https://doi.org/10.1103/PhysRevA.108.L051701
Abstract
We consider a system comprising two groups of quantum dimers placed in a common electromagnetic cavity and controlled by selectively applying a static external potential to one of the groups. We show that in the regime of deep strong coupling to vacuum electromagnetic fluctuations, the emergent photon-assisted interaction between the dimers, leads to a strongly nonlinear quantized cross-polarization response of the first, unbiased group of dimers to the potential applied to the second group. The total polarization shows a series of almost ideal steps whose number and position depends on the parity of the numbers of dimers in the groups. This nonperturbative effect is a distinctive feature of mesoscopic systems comprising a finite number of dimers and disappears in the thermodynamic limit which is commonly used in the description of the generalized Dicke models.