Quantum Optics Seminar by Dapeng Ding

Title: Cavity quantum electrodynamics with rare-earth ions in solids

Rare-earth ions in solids are of particular interest for quantum information storage and processing because of the long coherence times of the 4f states. In the past few years, substantial progress has been made by using ensembles of ions and single ions. However, the weak optical transitions within the 4f manifold pose a great challenge to the optical
interaction with a single rare-earth ion on a single-photon level. We demonstrate a 9-fold enhanced ion-light interaction (Purcell effect) in an integrated-optics-based, fibre-coupled silicon nitride ring resonator with implanted ytterbium ions. From the data we extract the 1D, 2D, and 3D contributions to the Purcell factor as well as the temperature-dependent
depolarisation and decoherence of the ions. The results indicate this cavity QED system has the potential of interfacing single rare-earth ions with single photons on a chip.