First principles predictions of magneto-optical data for semiconductor defects: the case of divacancy defects in 4H-SiC

TL;DR

This paper uses first-principles calculations to accurately predict magneto-optical properties of divacancy defects in 4H-SiC, aiding their identification and application in quantum technologies.

Contribution

It provides a detailed ab initio analysis of divacancy configurations in 4H-SiC, clarifying previous predictions and supporting defect identification for quantum applications.

Findings

Decisive identification of divacancy configurations in 4H-SiC

Clarification of differences in prior zero-phonon line predictions

Accurate ab initio data for quantum bit candidate properties

Abstract

Study and design of magneto-optically active single point defects in semiconductors are rapidly growing fields due to their potential in quantum bit and single photon emitter applications. Detailed understanding of the properties of candidate defects is essential for these applications, and requires the identification of the defects microscopic configuration and electronic structure. Multi-component semiconductors often host two or more non-equivalent configurations of point defects. These configurations generally exhibit similar electronic structure and basic functionalities, however, they differ in details that are of great importance whenever single defect applications are considered. Identification of non-equivalent configurations of point defects is thus essential for successful single defect manipulation and application. A promising way to identify defects is via comparison of experimental measurements and results of first-principle calculations. We investigate a possibility to produce accurate ab initio data for zero-phonon lines and hyperfine coupling parameters that are required for systematic quantum bit search. We focus on properties relevant for the possible use of the divacancy defect in quantum bits in 4H-SiC. We provide a decisive identification of divacancy configurations in 4H-SiC and clarify differences in prior predictions of 4H-SiC divacancy zero-phonon photoluminescence lines.