Absence of Entanglement Growth in Dicke Superradiance

Abstract

Dicke superradiance describes an ensemble of $N$ permutationally invariant two-level systems collectively emitting radiation with a peak radiated intensity scaling as $N^2$. Although individual Dicke states are typically entangled, the density matrix during superradiant decay is a mixture of such states, raising the subtle question of whether the total state is entangled or separable. We resolve this by showing analytically that for all $N$, starting from the fully excited state, the collective decay preserves separability for all times. This answers a longstanding question on the role of entanglement in Dicke superradiance and underscores that, despite collective dissipation, separable states remain separable under these dynamics.

6+16 pages,1+2 figures

References in corpus (10)

• Entanglement detection
• Observation of Dicke Superradiance for Two Artificial Atoms in a Cavity with High Decay Rate
• Detecting multiparticle entanglement of Dicke states
• Universality of Dicke superradiance in arrays of quantum emitters
• Entanglement and permutational symmetry
• Collective processes of an ensemble of spin-1/2 particles
• Separability of diagonal symmetric states: a quadratic conic optimization problem
• A complete hierarchy for the pure state marginal problem in quantum mechanics
• Observation of collective decay dynamics of a single Rydberg superatom
• Unraveling Dicke Superradiant Decay with Separable Coherent Spin States

Cited by in corpus (1)

• Initiation of Superradiance from Different Collective-Spin States