Enhancing cavity QED via anti-squeezing: synthetic ultra-strong coupling

TL;DR

This paper introduces a parametric driving technique that exponentially enhances light-matter coupling in cavity QED systems, enabling access to strong and ultra-strong coupling regimes for advanced quantum state preparation.

Contribution

The authors propose a novel method using two-photon parametric driving to exponentially increase coupling strength in cavity QED, facilitating ultra-strong coupling regimes from weak systems.

Findings

Enhanced coupling exceeds dissipative rates

Achieved ultra-strong coupling regime

Prepared highly entangled ground states

Abstract

We present and analyze a method where parametric (two-photon) driving of a cavity is used to exponentially enhance the light-matter coupling in a generic cavity QED setup, with time-dependent control. Our method allows one to enhance weak-coupling systems, such that they enter the strong coupling regime (where the coupling exceeds dissipative rates) and even the ultra-strong coupling regime (where the coupling is comparable to the cavity frequency). As an example, we show how the scheme allows one to use a weak-coupling system to adiabatically prepare the highly entangled ground state of the ultra-strong coupling system. The resulting state could be used for remote entanglement applications.