Cavity-enhanced zero-phonon emission from an ensemble of G centers in a silicon-on-insulator microring

TL;DR

This paper demonstrates cavity-enhanced zero-phonon emission from G centers in silicon-on-insulator microrings, achieving a fivefold emission increase via Purcell enhancement, with implications for integrated quantum photonics.

Contribution

The study introduces a method to enhance zero-phonon emission from G centers in SOI microrings using resonant cavity coupling, advancing integrated quantum photonics.

Findings

Resonant modes with Q factor ~3000 achieved at 1278 nm.

Zero-phonon line intensity increased by a factor of 5.

Low radiative yield (<10%) observed despite enhancement.

Abstract

We report successful incorporation of an ensemble of G centers in silicon-on-insulator (SOI) microrings using ion implantation and conventional nanofabrication. The coupling between the emitters and the resonant modes of the microrings is studied using continuous-wave and time-resolved microphotoluminescence (PL) experiments. We observe the resonant modes of the microrings on PL spectra, on the wide spectral range that is covered by G centers emission. By finely tuning the size of the microrings, we match their zero-phonon line at 1278 nm with a resonant mode of quality factor around 3000 and volume 7.2 (lambda over n)^3. The zero-phonon line intensity is enhanced by a factor of 5, both in continuous-wave and time-resolved measurements. This is attributed to the Purcell enhancement of zero-phonon spontaneous emission into the resonant mode and quantitatively understood considering the distribution of the G centers dipoles. Despite the enhancement of the zero-phonon emission, we do not observe any sizeable decrease of the average lifetime of the G centers, which points at a low radiative yield (<10%). We reveal the detrimental impact of parasitic defects in heavily implanted silicon, and discuss the perspectives for quantum electrodynamics experiments with individual color centers in lightly implanted SOI rings. Our results provide key information for the development of deterministic single photon sources for integrated quantum photonics.