Photonic devices fabricated from (111)-oriented single crystal diamond

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 vapor deposition of diamond in the presence of silicon to generate homogenous silicon vacancy color centers with emission properties that are superior to those in (100)-oriented diamond. We further use the diamond membranes to fabricate microring resonators with quality factors exceeding similar to 3000. Supported by finite-difference time-domain calculations, we discuss the advantages of (111)-oriented structures as building blocks for quantum nanophotonic devices.