Vacancy-cluster color centers in lithium fluoride have been studied in detail both theoretically and experimentally for over a century, giving rise to various applications in solid-state lasers, broadband photonic devices, and radiation dosimeters. These color centers are also attractive candidate platforms for applications in quantum information science, due to their spin properties and strong coupling to the crystal lattice, which allows their properties to be easily tuned. Here we present hybrid functional calculations of common vacancy defects in lithium fluoride, including their energetic, spin, and optical properties. We show that for a wide range of hybrid functional parameters tuned to match the experimental band gap, certain defects have little variation in their predicted optical properties. We further demonstrate that the parameters needed to satisfy the generalized Koopman's theorem and correctly position defect levels within the gap, can vary dramatically, even for different charge states of the same defect. Our work establishes the accuracy of the computationally lightweight hybrid-functional approach for predicting the optical and energetic properties of color centers in polar materials.
@article{arxiv.2412.21060,
title = {First-principles Spin and Optical Properties of Vacancy Clusters in Lithium Fluoride},
author = {Mariano Guerrero Perez and Keegan Walkup and Jordan Chapman and Pranshu Bhaumik and Giti A. Khodaparast and Brenden A. Magill and Patrick Huber and Vsevolod Ivanov},
journal= {arXiv preprint arXiv:2412.21060},
year = {2025}
}