Ultrastrongly dissipative quantum Rabi model

TL;DR

This paper explores the dynamics of cavity QED systems with ultrastrong light-matter coupling and dissipation, revealing how qubit dressing influences behavior and proposing experimental implementations.

Contribution

It introduces a non-perturbative analysis of dissipative ultrastrong coupling in cavity QED using the dynamical polaron ansatz and MPS simulations.

Findings

Critical coupling for Rabi oscillations identified

Qubit dressing by cavity and dissipation demonstrated

Potential circuit QED implementation proposed

Abstract

We discuss the equilibrium and out of equilibrium dynamics of cavity QED in presence of dissipation beyond the standard perturbative treatment of losses. Using the dynamical polaron \emph{ansatz} and Matrix Product State simulations, we discuss the case where both light-matter $g$-coupling and system-bath interaction are in the ultrastrong coupling regime. We provide a critical $g$ for the onset of Rabi oscillations. Besides, we demonstrate that the qubit is \emph{dressed} by the cavity and dissipation. That such dressing governs the dynamics and, thus, it can be measured. Finally, we sketch an implementation for our theoretical ideas within circuit QED technology.