English

Quantum correlated steady states under competing collective and individual decay

Quantum Physics 2025-12-08 v2

Abstract

Collective dissipation can generate useful quantum correlations, while ubiquitous individual decay destroys them. We study the interplay between these two competing processes considering a driven system of many spins (``atoms") undergoing both collective and individual dissipation (``radiation"). In steady state and depending on drive, we find that the system exhibits a first-order phase transition and quantum bistability: its quantum state is a mixture of two many-body states associated with the two competing decay processes. Accordingly, one of these states closely resembles a correlated ``coherently radiating spin state" (CRSS) -- the solution of purely collective dissipation -- exhibiting spin-squeezing entanglement. We predict dynamical switching between the two stable states, manifest as many-body quantum jumps in the various observables of spin and radiation. Macroscopically, the switching rate tends to vanish and the system can reside in a correlated CRSS for long times. This reveals how correlated dissipative physics emerges at the presence of decorrelating individual decay, opening a path for unlocking collective dissipation phenomena in realistic quantum platforms and applications. We discuss consequences for experiments in collective radiation.

Keywords

Cite

@article{arxiv.2404.02134,
  title  = {Quantum correlated steady states under competing collective and individual decay},
  author = {Nikita Leppenen and Ephraim Shahmoon},
  journal= {arXiv preprint arXiv:2404.02134},
  year   = {2025}
}

Comments

Significantly extended version. 21 pages, 14 figures