Anomalous light shift through quantum jumps in quasi-resonant Rayleigh scattering

TL;DR

This paper reports an observation of an unusual light shift in Rb 85 atoms caused by quantum jumps, where the Larmor frequency increases with drive strength, with shifts up to 1% per photon, revealing stochastic phase accumulation.

Contribution

It demonstrates a novel anomalous light shift linked to quantum jumps in a cavity QED system, expanding understanding of light-matter interactions at the quantum level.

Findings

Observed anomalous light shift up to 1% per photon.

Linked the shift to phase accumulation from quantum jumps.

Demonstrated stochastic broadening of the shift.

Abstract

An anomalous light shift in the precession of a ground-state Zeeman coherence is observed: the Larmor frequency increases with the strength of a drive that is blue (red) detuned from a transition out of the lower (upper) energy level. Our measurements are made on Rb 85 atoms traversing an optical cavity containing a few photons; shifts as large as 1% per photon are recorded. The anomalous shift arises from an accumulation of phase driven by quantum jumps. It is stochastic and accompanied by broadening.