"Spontaneous avalanche dephasing in large Rydberg ensembles" published

Our follow-up paper to the anamalous broadening work explores the dynamics of the black-body-induced runaway broadening process. Such broadening has serious implications for many proposals to coherently use Rydberg interactions, particularly Rydberg dressing proposals. The dephasing arises as a runaway process where the production of the first contaminant atoms facilitates the creation of more contaminant atoms.  Using a pump-probe technique, we create an excess “pump” Rydberg population and probe its effect with a different “probe” Rydberg transition. We observe a reduced resonant pumping rate and an enhancement of the excitation on both sides of the transition as atoms are added to the pump state. We also observe a time scale for population growth that is significantly shorter than predicted by homogeneous mean-field models, as expected from a clustered growthmechanismwhere high-order correlations dominate the dynamics. These results support our earlier work and confirm that the time scale for the onset of dephasing is reduced by a factor which scales as the inverse of the atom number. In addition, we discuss several approaches to minimize these effects of spontaneous broadening, including stroboscopic techniques and operating at cryogenic temperatures. It is challenging to avoid the unwanted broadening effects, but under some conditions they can be mitigated. The result was published in Physical Review A:  https://journals.aps.org/pra/abstract/10.1103/PhysRevA.96.053409