Quantum error correction of motional dephasing using optical dressing

Abstract

Maintaining the coherence in quantum systems is interesting in both fundamental physics and quantum information processing. In particular, suppressing the dephasing caused by thermal fluctuations in quantum systems can potentially enable functional quantum devices. Techniques to reduce motional dephasing of quantum superpositions include spin echo and bang-bang. In this paper, we demonstrate the effectiveness of a novel protocol on a collective quantum superposition state known as a Rydberg polariton. These collective states are potentially important in the context of single photon sources, optical transistor, all-optical quantum gates and fast read-out of quantum information. However progress in Rydberg polariton quantum technology has been hindered by fast motional dephasing on which no effective methods exist for undoing it. Here, we show how our protocol via optical dressing using Raman lasers cancels dephasing and enhances coherence times by more than an order of magnitude.