Coherent spectroscopy of rare-earth-ion doped whispering-gallery mode resonators

TL;DR

This study investigates the properties of Pr3+:Y2SiO5 whispering gallery mode resonators to explore their potential for strong coupling in cavity QED, confirming theoretical predictions and analyzing ion-resonator interactions.

Contribution

It provides the first detailed measurement of cavity QED parameters in rare-earth-ion doped whispering gallery resonators using photon echoes.

Findings

Good agreement between measurements and theory

Physical fabrication does not impair ion properties

Observation of optical bistability and normal-mode splitting

Abstract

We perform an investigation into the properties of Pr3+:Y2SiO5 whispering gallery mode resonators as a first step towards achieving the strong coupling regime of cavity QED with rare-earth-ion doped crystals. Direct measurement of cavity QED parameters are made using photon echoes, giving good agreement with theoretical predictions. By comparing the ions at the surface of the resonator to those in the center it is determined that the physical process of making the resonator does not negatively affect the properties of the ions. Coupling between the ions and resonator is analyzed through the observation of optical bistability and normal-mode splitting.