Deterministic steady-state subradiance within a single-excitation basis

TL;DR

This paper presents a theoretical framework for achieving perfect steady-state subradiance and multipartite entanglement within a single-excitation basis, with potential applications in quantum information processing.

Contribution

It introduces a novel state space enabling perfect subradiance and derives analytical steady-state solutions for all-to-all and quasi-all-to-all coupling scenarios.

Findings

Analytical steady-state solutions for single-excitation initial states.

Validation using emitters in photonic crystal slabs with bound states.

Framework predicts long-lived multipartite entanglement dynamics.

Abstract

Subradiance shows promising applications in quantum information, yet its realization remains more challenging than superradiance due to the need to suppress various decay channels. This study introduces a state space within a single-excitation basis with perfect subradiance and genuine multipartite quantum entanglement resources for the all-to-all case. Utilizing the quantum jump operator method, we also provide an analytical derivation of the system's steady final state for any single-excitation initial state. Additionally, we determine the approximate final state in the quasi-all-to-all coupling scenario. As an illustrative example, we evaluate the coupling and dynamical properties of emitters in a photonic crystal slab possessing an ultra-high quality bound state in the continuum, thereby validating the efficacy of our theoretical approach. This theoretical framework facilitates the analytical prediction of dynamics for long-lived multipartite entanglement while elucidating a pathway toward realizing autonomous subradiance in atomic systems.