Anomalous excitation facilitation in inhomogeneously broadened Rydberg gases

TL;DR

This paper explores a novel excitation mechanism called anomalous facilitation in inhomogeneously broadened Rydberg gases, occurring on the opposite side of resonance due to inhomogeneous broadening, even in scenarios where traditional facilitation is absent.

Contribution

It introduces and analyzes the concept of anomalous facilitation caused by inhomogeneous broadening in Rydberg gases, expanding understanding of excitation dynamics beyond standard models.

Findings

Anomalous facilitation occurs on the blue detuned side with attractive interactions.

Inhomogeneous broadening enables facilitation outside usual resonance conditions.

Experimental conditions for observing anomalous facilitation are identified.

Abstract

When atomic gases are laser driven to Rydberg states in an off resonant way, a single Rydberg atom may enhance the excitation rate of surrounding atoms. This leads to a facilitated excitation referred to as Rydberg anti-blockade. In the usual facilitation scenario, the detuning of the laser from resonance compensates the interaction shift. Here, we discuss a different excitation mechanism, which we call anomalous facilitation. This occurs on the "wrong side" of the resonance and originates from inhomogeneous broadening. The anomalous facilitation may be seen in experiments of attractively interacting atoms on the blue detuned side, where facilitation is not expected to appear.