Dissipation induced dipole blockade and anti-blockade in driven Rydberg systems

TL;DR

This paper investigates how contaminant Rydberg atoms induce blockade and anti-blockade effects in driven Rydberg systems, combining theoretical models and experiments to understand their influence on Rydberg population dynamics.

Contribution

It introduces two theoretical approaches to model contaminant-induced effects and experimentally verifies the transition in Rydberg population dependence on Rabi frequency.

Findings

Qualitative agreement between cumulant expansion and experiments for blockade radius.

Observation of a crossover from quadratic to linear Rydberg population dependence with increasing density.

Rate equations accurately predict steady-state Rydberg populations across different conditions.

Abstract

We study theoretically and experimentally the competing blockade and anti-blockade effects induced by spontaneously generated contaminant Rydberg atoms in driven Rydberg systems. These contaminant atoms provide a source of strong dipole-dipole interactions and play a crucial role in the system's behavior. We study this problem theoretically using two different approaches. The first is a cumulant expansion approximation, in which we ignore third-order and higher connected correlations. Using this approach for the case of resonant drive, a many-body blockade radius picture arises, and we find qualitative agreement with previous experimental results. We further predict that as the atomic density is increased, the Rydberg population's dependence on Rabi frequency will transition from quadratic to linear dependence at lower Rabi frequencies. We study this behavior experimentally by observing this crossover at two different atomic densities. We confirm that the larger density system has a smaller crossover Rabi frequency than the smaller density system. The second theoretical approach is a set of phenomenological inhomogeneous rate equations. We compare the results of our rate equation model to the experimental observations in [E. A. Goldschmidt, et al., PRL 116, 113001 (2016)] and find that these rate equations provide quantitatively good scaling behavior of the steady-state Rydberg population for both resonant and off-resonant drive.