Many-body gap protection of motional dephasing of an optical clock transition

TL;DR

This paper demonstrates that many-body interactions in a high-finesse optical cavity can create an energy gap that suppresses motional dephasing in an optical clock transition, enhancing coherence for quantum metrology.

Contribution

It introduces a collective many-body gap mechanism in an optical cavity to reduce Doppler dephasing, providing a new approach for improving optical quantum sensors and simulations.

Findings

Suppression of Doppler dephasing in strontium optical clock transition.

Creation of a many-body energy gap that increases with atom number.

Enhanced coherence times for quantum metrology applications.

Abstract

Quantum simulation and metrology with atoms, ions, and molecules often rely on using light fields to manipulate their internal states. The absorbed momentum from the light fields can induce spin-orbit coupling and associated motional-induced (Doppler) dephasing, which may limit the coherence time available for metrology and simulation. We experimentally demonstrate the suppression of Doppler dephasing on a strontium optical clock transition by enabling atomic interactions through a shared mode in a high-finesse optical ring cavity. The interactions create a many-body energy gap that increases with atom number, suppressing motional dephasing when it surpasses the dephasing energy scale. This collective approach offers an alternative to traditional methods, like Lamb-Dicke confinement or M\"ossbauer spectroscopy, for advancing optical quantum sensors and simulations.