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Quantum 2.0 Conference and Exhibition

Mode entanglement created by interacting superradiant emitters

Chen Mechel, Offek Tziperman, Alexey A. Gorlach, Ido E. Kaminer

Published Jan 1, 2024• 0 citations
Publisher

Abstract

We show that interacting quantum emitters coupled to a waveguide or any bath of optical-modes emit mode-entangled light. Controlling this entanglement could create useful multi-mode pure states, although each mode has thermal statistics.
DOI
10.1364/quantum.2024.qth4a.3

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The many-body decay of extended collections of two-level systems remains an open problem. Here, we investigate whether an array of emitters coupled to a one-dimensional bath undergoes Dicke superradiance. This is a process whereby a completely inverted system becomes correlated via dissipation, leading to the release of all the energy in the form of a rapid photon burst. We derive the minimal conditions for the burst to happen as a function of the number of emitters, the chirality of the waveguide, and the single-emitter optical depth, both for ordered and disordered ensembles. Many-body superradiance occurs because the initial fluctuation that triggers the emission is amplified throughout the decay process. In one-dimensional baths, this avalanchelike behavior leads to a spontaneous mirror symmetry breaking, with large shot-to-shot fluctuations in the number of photons emitted to the left and right. Superradiant bursts may thus be a smoking gun for the generation of correlated photon states of exotic quantum statistics.