Homoepitaxial Growth of Single Crystal Diamond Membranes for Quantum Information Processing

TL;DR

This paper presents a scalable microwave CVD method for growing thin, high-quality single crystal diamond membranes suitable for quantum information devices, demonstrating promising optical and spin properties.

Contribution

It introduces a novel, scalable epitaxial growth technique for diamond membranes that facilitates quantum device fabrication.

Findings

Membranes show bright luminescence and good NV center coherence.

Microdisk cavities achieve quality factors up to 3000.

Method enables scalable diamond device fabrication.

Abstract

Fabrication of devices designed to fully harness the unique properties of quantum mechanics through their coupling to quantum bits (qubits) is a prominent goal in the field of quantum information processing (QIP). Among various qubit candidates, nitrogen vacancy (NV) centers in diamond have recently emerged as an outstanding platform for room temperature QIP. However, formidable challenges still remain in processing diamond and in the fabrication of thin diamond membranes, which are necessary for planar photonic device engineering. Here we demonstrate epitaxial growth of single crystal diamond membranes using a conventional microwave chemical vapor deposition (CVD) technique. The grown membranes, only a few hundred nanometers thick, show bright luminescence, excellent Raman signature and good NV center electronic spin coherence times. Microdisk cavities fabricated from these membranes exhibit quality factors of up to 3000, overlapping with NV center emission. Our methodology offers a scalable approach for diamond device fabrication for photonics, spintronics, optomechanics and sensing applications.