Hyperfine Interaction of the Group IV Color Centers

Abstract

The group IV-negative color centers (SiV⁻, GeV⁻, SnV⁻) are one of the leading candidates for spin-photon interfaces for use in quantum information technologies. They feature highly coherent optical transitions, as well as native electron and nuclear spins that can be used as quantum memories. While the optical and electronic properties of these defects have been studied extensively in previous works, a detailed theory of the hyperfine coupling to the nuclear spin is lacking. This work presents a complete theoretical model of the hyperfine coupling to the intrinsic dopant nucleus in the group IV-negative color centers, complete with ab-initio theoretical predictions of the hyperfine coupling strength, and supported by experimental observation in an isotopically engineered sample. The theoretical model explains the observed hyperfine features well, providing a foundation for future work to use the intrinsic nuclear spin in quantum protocols.