# Characterization and formation of NV centers in 3C, 4H and 6H SiC: an \emph{ab initio} study

## TL;DR

This study uses ab initio calculations to characterize NV centers in various SiC polytypes, providing insights into their properties, formation, and potential as quantum bits, complemented by new experimental data.

## Contribution

It offers a detailed theoretical analysis of NV defect configurations in SiC polytypes and presents new experimental data, advancing understanding of their properties for quantum applications.

## Key findings

- Identified different NV defect configurations in SiC polytypes.
- Provided ionization energies and optical excitation thresholds for NV centers.
- Discussed challenges in producing NV defects with desirable spin properties.

## Abstract

Fluorescent paramagnetic defects in solids have become attractive systems for quantum information processing in the recent years. One of the leading contenders is the negatively charged nitrogen-vacancy defect in diamond with visible emission but alternative solution in technologically mature host is an immediate quest for many applications in this field. It has been recently found that various polytypes of silicon carbide (SiC), that are standard semiconductors with wafer scale technology, can host nitrogen-vacancy defect (NV) that could be an alternative qubit candidate with emission in the near infrared region. However, it is much less known about this defect than its counterpart in diamond. The inequivalent sites within a polytype and the polytype variations offer a family of NV defects. However, there is an insufficient knowledge on the magneto-optical properties of these configurations. Here we carry out density functional theory calculations, in order to characterize the numerous forms of NV defects in the most common polytypes of SiC including 3C, 4H and 6H, and we also provide new experimental data in 4H SiC. Our calculations mediate the identification of individual NV qubits in SiC polytypes. In addition, we discuss the formation of NV defects in SiC with providing detailed ionization energies of NV defect in SiC which reveals the critical optical excitation energies for ionizing this qubits in SiC. Our calculations unravel the challenges to produce NV defects in SiC with a desirable spin bath.