Coherent pumping of a Mott insulator: Fermi golden rule versus Rabi oscillations

TL;DR

This paper investigates how periodic modulation of hopping in a fermionic Mott insulator induces either coherent Rabi oscillations or incoherent pumping, revealing the interplay between these dynamics in many-body quantum systems.

Contribution

It introduces a model mapping the Mott insulator to a two-level system exhibiting Rabi oscillations and compares coherent versus incoherent pumping mechanisms.

Findings

Deep in the insulating phase, the system shows coherent Rabi oscillations.

Coupling to other degrees of freedom causes damping of Rabi oscillations.

Incoherent pumping into a broad continuum provides an alternative dynamical description.

Abstract

Cold atoms provide a unique arena to study many-body systems far from equilibrium. Furthermore, novel phases in cold atom systems are conveniently investigated by dynamical probes pushing the system out of equilibrium. Here, we discuss the pumping of doubly-occupied sites in a fermionic Mott insulator by a periodic modulation of the hopping amplitude. We show that deep in the insulating phase the many-body system can be mapped onto an effective two-level system which performs coherent Rabi oscillations due to the driving. Coupling the two-level system to the remaining degrees of freedom renders the Rabi oscillations damped. We compare this scheme to an alternative description where the particles are incoherently pumped into a broad continuum.