Accessing Rydberg-dressed interactions using many-body Ramsey dynamics

TL;DR

This paper demonstrates how Ramsey spectroscopy can be used to observe and analyze Rydberg-dressed interactions within experimentally feasible lifetimes, revealing unique quantum dynamics and providing a theoretical framework for understanding these interactions.

Contribution

It introduces a novel Ramsey spectroscopy scheme for Rydberg-dressed interactions, deriving an exact solution for the associated Ising spin model and highlighting unique dynamical features.

Findings

Ramsey spectroscopy can effectively probe Rydberg-dressed interactions.

The derived model accurately predicts experimental results, including ultrafast Rydberg experiments.

Spin echo can enhance coherence decay rates in Rydberg systems.

Abstract

We demonstrate that Ramsey spectroscopy can be used to observe Rydberg-dressed interactions. In contrast to many prior proposals, our scheme operates comfortably within experimentally measured lifetimes, and accesses a regime where quantum superpositions are crucial. The key idea is to build a spin-1/2 from one level that is Rydberg-dressed and another that is not. These levels may be hyperfine or long-lived electronic states. An Ising spin model governs the Ramsey dynamics, for which we derive an exact solution. Due to the structure of Rydberg interactions, the dynamics differs significantly from that in other spin systems. As one example, spin echo can increase the rate at which coherence decays. The results also apply to bare (undressed) Rydberg states as a special case, for which we quantitatively reproduce recent ultrafast experiments without fitting.