Photonic devices fabricated from (111) oriented single crystal diamond

TL;DR

This paper presents a new method for fabricating optically-active (111)-oriented diamond membranes with superior silicon vacancy centers and high-quality microring resonators, advancing quantum photonic device development.

Contribution

It introduces a fabrication process for (111)-oriented diamond membranes and demonstrates their advantages for quantum nanophotonics.

Findings

Silicon vacancy centers in (111) diamond show improved emission properties.

Microring resonators with quality factors over 3000 were fabricated.

(111) orientation offers advantages for quantum photonic applications.

Abstract

Diamond is a material of choice in the pursuit of integrated quantum photonic technologies. So far, the majority of photonic devices fabricated from diamond, are made from (100)-oriented crystals. In this work, we demonstrate a methodology for the fabrication of optically-active membranes from (111)-oriented diamond. We use a liftoff technique to generate membranes, followed by chemical vapour deposition of diamond in the presence of silicon to generate homogenous silicon vacancy colour centers with emission properties that are superior to those in (100)-oriented diamond. We further use the diamond membranes to fabricate high quality microring resonators with quality factors exceeding ~ 3000. Supported by finite difference time domain calculations, we discuss the advantages of (111) oriented structures as building blocks for quantum nanophotonic devices.