Coupling of erbium dopants to yttrium orthosilicate photonic crystal cavities for on-chip optical quantum memories

TL;DR

This paper demonstrates the coupling of erbium dopants in yttrium orthosilicate to photonic crystal cavities, enhancing optical properties for potential on-chip quantum memory applications in the telecom band.

Contribution

It introduces a novel fabrication method for coupling erbium ions to photonic crystal cavities directly in the host crystal.

Findings

Reduced photoluminescence lifetime

Enhanced optical depth in microns-long devices

Potential for on-chip quantum memories

Abstract

Erbium dopants in crystals exhibit highly coherent optical transitions well suited for solid-state optical quantum memories operating in the telecom band. Here we demonstrate coupling of erbium dopant ions in yttrium orthosilicate to a photonic crystal cavity fabricated directly in the host crystal using focused ion beam milling. The coupling leads to reduction of the photoluminescence lifetime and enhancement of the optical depth in microns-long devices, which will enable on-chip quantum memories.