Defects in Diamond and Quantum Dot Spin Dynamics

Quantum defects in solids such as SiV(0) in diamond are a promising route for optical qubits and quantum networking systems. The zero-phonon line emission of SiV(0) is just under 1 micron, near the threshold for telecommunications transmission wavelengths. With the application of strain, the electronic energy surfaces change, potentially yielding more optimal wavelengths in telecom bands. To describe the dependence of the ground- and excited-state electronic energy surfaces, an accurate description of the electronic states of open-shell quantum defects in solids is required. This is, however, an ongoing challenge in electronic structure theory. The recently-developed Spin-Flip Bethe-Salpeter Equation (SF-BSE) is a promising approach to describe the states and energies for open-shell defects in solids [Barker and Strubbe, arXiv:2207.04549]. Previous work indicates comparable agreement with Full-Configuration Interaction-based Quantum Defect Embedding Theory, for the SiV(0) defect in diamond. Building on the quantitative success of SF-BSE applied to SiV(0), we now consider the system under strain, and we discuss implications for quantum networking applications.