Single-Particle Decoherence Can Improve Spin-Squeezing Generated In Collective Dynamics

TL;DR

This paper demonstrates that spontaneous emission, typically seen as detrimental, can actually enhance spin-squeezing in collective quantum systems, due to a dissipative phase transition, with implications for quantum sensing technologies.

Contribution

It reveals that single-particle decoherence can improve spin-squeezing in collective dynamics, a counter-intuitive finding that leverages dissipative phase transitions.

Findings

Spontaneous emission enhances achievable spin-squeezing.

Dissipative phase transition enables self-tuning of the system.

Results applicable to quantum sensors like cavity-QED and trapped ions.

Abstract

We study the generation of spin-squeezing in arrays of long-lived dipoles subject to collective emission, coherent drive, elastic interactions, and spontaneous emission. Counter-intuitively, it is found that the introduction of spontaneous emission leads to an enhancement of the achievable spin-squeezing, relative to that which emerges in the steady-state of the purely collective dynamics for the same model parameters. This behavior is connected to the dynamical self-tuning of the system through a dissipative phase transition that is present in the collective system alone. Our findings will be applicable to next-generation quantum sensors harnessing correlated quantum matter, including cavity-QED and trapped ion systems.