Correlated emission lasing in harmonic oscillators coupled via a single three-level artificial atom

TL;DR

This paper demonstrates correlated emission lasing in two harmonic oscillators coupled through a controllable three-level artificial atom, achieving highly correlated two-mode lasing with linewidths far below the standard limit.

Contribution

It introduces a novel method of inducing correlated emission lasing in harmonic oscillators via a superconducting artificial atom, surpassing traditional linewidth limits.

Findings

Two-mode correlated emission lasing achieved

Linewidths narrower than Schawlow-Townes limit

Strong correlation between different color lasing fields

Abstract

A single superconducting artificial atom provides a unique basis for coupling electromagnetic fields and photons hardly achieved with a natural atom. Bringing a pair of harmonic oscillators into resonance with transitions of the three-level atom converts atomic spontaneous processes into correlated emission dynamics. We demonstrate two-mode correlated emission lasing on harmonic oscillators coupled via the fully controllable three-level artificial atom. Correlation of two different color emissions reveals itself as equally narrowed linewiths and quench of their mutual phase-diffusion. The mutual linewidth is more than four orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates the two-mode fields are strongly correlated.