$\textit{Ab initio}$ and group theoretical study of properties of the $\text{C}_\text{2}\text{C}_\text{N}$ carbon trimer defect in h-BN

TL;DR

This study combines group theory and DFT calculations to predict the properties of a specific carbon trimer defect in h-BN, with implications for quantum information technologies.

Contribution

It provides a detailed theoretical analysis of the $ ext{C}_2 ext{C}_N$ defect's electronic states, transitions, and magnetic properties, advancing understanding of its quantum potential.

Findings

Predicted multi-electron states and optical transitions of the defect.

Simulated ODMR signals and correlation functions for quantum applications.

Identified the defect's suitability for quantum sensing and communication.

Abstract

Hexagonal boron nitride (h-BN) is a promising platform for quantum information processing due to its potential to host optically active defects with attractive optical and spin properties. Recent studies suggest that carbon trimers might be the defect responsible for single-photon emission in the visible spectral range in h-BN. In this theoretical study, we combine group theory together with density functional theory (DFT) calculations to predict the properties of the neutral $\text{C}_\text{2}\text{C}_\text{N}$ carbon trimer defect. We find the multi-electron states of this defect along with possible radiative and non-radiative transitions assisted by the spin-orbit and the spin-spin interactions. We also investigate the Hamiltonian for external magnetic field and ground-state hyperfine interactions. Lastly, we use the results of our investigation in a Lindblad master equation model to predict an optically detected magnetic resonance (ODMR) signal and the $g^2(\tau)$ correlation function. Our findings can have important outcomes in quantum information applications such as quantum repeaters used in quantum networks and quantum sensing.