Superradiance of non-Dicke states

TL;DR

This paper demonstrates that superradiance can occur from non-Dicke states with nonzero dipole moments, expanding the understanding of conditions under which superradiant bursts can happen.

Contribution

It reveals that superradiance is not limited to Dicke states and shows how phase dispersion reduction leads to superradiance in non-Dicke states.

Findings

Superradiance can originate from non-Dicke states with nonzero dipole moments.

Reduction in quantum phase dispersion causes constructive interference leading to superradiance.

Both Dicke and non-Dicke states exhibit superradiance due to phase dispersion effects.

Abstract

In 1954, Dicke predicted that a system of quantum emitters confined to a subwavelength volume would produce a superradiant burst. For such a burst to occur, the emitters must be in the special Dicke state with zero dipole moment. We show that a superradiant burst may also arise for non-Dicke initial states with nonzero dipole moment. Both for Dicke and non-Dicke initial states, superradiance arises due to a decrease in the dispersion of the quantum phase of the emitter state. For non-Dicke states, the quantum phase is related to the phase of long-period envelopes which modulate the oscillations of the dipole moments. A decrease in dispersion of the quantum phase causes a decrease in the dispersion of envelope phases that results in constructive interference of the envelopes and the superradiant burst.