[Seminar] "Semiclassical Phase-Space Dynamics of Emitter Ensembles with Local Dissipation" Dr. Lewis Ruks, Theoretical Quantum Physics Research Group, NTT Basic Research Laboratories

Speaker

Lewis Ruks, Research Scientist, Theoretical Quantum Physics Research Group, Basic Research Laboratories

Abstract

We establish a semiclassical phase-space description of permutation-invariant emitter ensembles with local dissipation, representing each ensemble by four phase-space variables associated with a collective spin of variable length. This description is obtained through a Wigner–Moyal expansion, yielding at leading order a scalable truncated Wigner approximation (TWA) whose stochastic dynamics can be simulated using classical Monte Carlo methods. We illustrate, in a model of pumped bad-cavity superradiance, that the TWA captures spin squeezing and subradiance, and improves on common approximations including cumulant expansions. We cast a class of spatially extended emitter systems as interacting ensembles to show how fluctuations captured in the TWA reshape directional cooperative emission beyond mean-field predictions, in a pumped chain containing tens of thousands of emitters. Our results identify a semiclassical limit for a class of microscopic quantum-optical models comprising emitter ensembles and offer a route towards studying their collective phenomena. (arXiv:2602.14025)

Looking forward to seeing many of you at the seminar!

Quantum Systems Unit