Cavity Enhanced Emission from Telecom Rare-Earth System in Colloidal Host
Abstract
Erbium incorporated in a ceria (CeO2) host offers strong potential as a spin qubit platform, providing a pathway toward telecom-compatible quantum memory. But erbium is a dim emitter due to its long excited state lifetime. Methods to enhance its emission rate and efficiency through nanophotonic cavity integration are therefore essential. In this work, we demonstrate cavity-enhanced emission from erbium doped CeO2. We couple colloidally synthesized erbium doped CeO2 nanocrystals to a silicon nanobeam cavity and show a 30-fold improvement in emitter brightness combined with a 2-fold lifetime enhancement. We estimate a lower bound of 12 for the Purcell factor of cavity-coupled emitters after accounting for non-radiative decay. These results pave the way towards utilizing colloidally synthesized optically addressable spin qubits emitting at telecom wavelength for quantum networking and distributed quantum computing.
Cite
@article{arxiv.2510.01139,
title = {Cavity Enhanced Emission from Telecom Rare-Earth System in Colloidal Host},
author = {Purbita Purkayastha and Cristian Gonzalez and Cameron Mollazadeh and Chang-Min Lee and Fariba Islam and Abhijit Biswas and Michael F. Toney and Christopher B. Murray and Edo Waks},
journal= {arXiv preprint arXiv:2510.01139},
year = {2025}
}