Investigation of oxygen-vacancy complexes in diamond by means of \textit{ab initio} calculations

TL;DR

This study uses ab initio calculations to analyze oxygen-vacancy complexes in diamond, aiming to identify potential quantum memory centers, and finds that most are unlikely candidates for the ST1 color center, but a metastable complex shows promising properties.

Contribution

The paper provides a systematic first-principles investigation of oxygen-vacancy defects in diamond, identifying their spin states and magnetooptical properties relevant for quantum memory applications.

Findings

Most oxygen-vacancy defects have high-spin ground states, ruling them out as ST1 center candidates.

A high-spin metastable oxygen-vacancy complex is identified and characterized.

Results suggest specific defects for experimental verification in quantum information science.

Abstract

Point defects in diamond may act as quantum bits. Recently, oxygen-vacancy related defects have been proposed to the origin of the so-called ST1 color center in diamond that can realize a long-living solid-state quantum memory. Motivated by this proposal we systematically investigate oxygen-vacancy complexes in diamond by means of first principles density functional theory calculations. We find that all the considered oxygen-vacancy defects have a high-spin ground state in their neutral charge state, which disregards them as an origin for the ST1 color center. We identify a high-spin metastable oxygen-vacancy complex and characterize their magnetooptical properties for identification in future experiments.