High-Q optical nanocavities in bulk single-crystal diamond

TL;DR

This paper demonstrates the fabrication of high-quality factor optical nanocavities in bulk single-crystal diamond using angled-etching, enabling advanced applications in quantum optics, sensing, and nonlinear optics.

Contribution

It introduces a novel fabrication method for high-Q diamond nanocavities in bulk diamond, overcoming previous limitations in material processing.

Findings

Optical quality factors exceeding 10^5 achieved.

Devices operate across visible and telecom wavelengths.

Potential applications include quantum information and sensing.

Abstract

Single-crystal diamond, with its unique optical, mechanical and thermal properties, has emerged as a promising material with applications in classical and quantum optics. However, the lack of heteroepitaxial growth and scalable fabrication techniques remain major limiting factors preventing more wide-spread development and application of diamond photonics. In this work, we overcome this difficulty by adapting angled-etching techniques, previously developed for realization of diamond nanomechanical resonators, to fabricate racetrack resonators and photonic crystal cavities in bulk single-crystal diamond. Our devices feature large optical quality factors, in excess of 10^5, and operate over a wide wavelength range, spanning visible and telecom. These newly developed high-Q diamond optical nanocavities open the door for a wealth of applications, ranging from nonlinear optics and chemical sensing, to quantum information processing and cavity optomechanics.