Periodic quantum Rabi model with cold atoms at deep strong coupling

TL;DR

This paper experimentally demonstrates the periodic quantum Rabi model using cold atoms in deep strong coupling, revealing collapse and revival phenomena at extreme coupling conditions, thus advancing quantum simulation capabilities.

Contribution

It provides the first experimental realization of the periodic quantum Rabi model with cold atoms in the deep strong coupling regime, mapping atomic dynamics to this generalized model.

Findings

Observation of atomic dynamics beyond standard quantum Rabi physics.

Evidence of collapse and revival of the initial state at extreme coupling.

Validation of theoretical predictions for the periodic quantum Rabi model.

Abstract

The quantum Rabi model describes the coupling of a two-state system to a bosonic field mode. Recent theoretical work has pointed out that a generalized periodic version of this model, which maps onto Hamiltonians applicable in superconducting qubit settings, can be quantum simulated with cold trapped atoms. Here, we experimentally demonstrate atomic dynamics predicted by the periodic quantum Rabi model far in the deep strong coupling regime. The two-state system is represented by two Bloch bands of cold atoms in an optical lattice, and the bosonic mode by oscillations in a superimposed optical dipole trap potential. The observed dynamics beyond the usual quantum Rabi physics becomes relevant when the edge of the Brillouin zone is reached, and evidence for collapse and revival of the initial state is revealed at extreme coupling conditions.