Controlled Dicke Subradiance from a Large Cloud of Two-Level Systems

TL;DR

This paper demonstrates that a dilute cloud of cold atoms can effectively exhibit and control subradiance, a fragile quantum interference effect, in free space, advancing understanding of light-matter interactions.

Contribution

It introduces a new experimental platform using cold atomic clouds to observe and manipulate subradiance in free space, overcoming previous decoherence challenges.

Findings

Observation of subradiance in cold atomic clouds

Control mechanisms for subradiant states demonstrated

Enhanced understanding of light trapping in quantum systems

Abstract

Dicke superradiance has been observed in many systems and is based on constructive interferences between many scattered waves. The counterpart of this enhanced dynamics, subradiance, is a destructive interference effect leading to the partial trapping of light in the system. In contrast to the robust superradiance, subradiant states are fragile and spurious decoherence phenomena hitherto obstructed the observation of such metastable states. We show that a dilute cloud of cold atoms is an ideal system to look for subradiance in free space and study various mechanisms to control this subradiance.