Parity-Symmetry-Protected Bundle Emission

TL;DR

This paper demonstrates symmetry-protected multi-photon bundle emission in a cavity QED system under ultrastrong coupling, showing control over emission patterns via parity symmetry and extending multi-photon physics into new regimes.

Contribution

It introduces the concept of symmetry-protected bundle emission in the ultrastrong coupling regime, highlighting control over photon emission patterns through parity symmetry manipulation.

Findings

Parity symmetry permits only even-photon super-Rabi oscillations.

Dissipation suppresses odd-photon bundle emissions, enhancing purity.

Magnetic field control switches between even and odd photon bundle emissions.

Abstract

We demonstrate symmetry protected bundle emission in the cavity QED system under the ultrastrong coupling regime. Parity symmetry of Rabi model only permits the super-Rabi oscillations with periodic generation of even photons in cavity, which is realized by the laser driven flip of qubit and the parity conserved transitions induced by Rabi interaction. Combined with dissipation, only 2$n$-photon correlated emissions are allowed, and the corresponding purities are significantly enhanced by the parity symmetry, due to the almost perfect suppression of bundle emissions with odd correlated photons. The switching of bundle emissions between even and odd correlated photons can be controlled by manipulating the parity symmetry of system with an added magnetic field. This work extends multi-photon bundle emission to the ultrastrong coupling regime, and offers the prospect of exploring symmetry-protected multi-quanta physics.