First-principles Studies of Strongly Correlated States in Defect Spin Qubits in Diamond

TL;DR

This paper employs a new quantum embedding approach to perform first-principles calculations on spin defects in diamond, aiming to understand their strongly correlated states for quantum computing applications.

Contribution

It introduces a quantum embedding theory for calculating strongly correlated states of defect spins in diamond, enabling efficient solutions on classical and quantum computers.

Findings

Predicted properties of neutral group-IV vacancy complexes in diamond.

Characterized their strongly-correlated spin-singlet and triplet excited states.

Provided insights for experimental optical manipulation of defect spins.

Abstract

Using a recently developed quantum embedding theory, we present first principles calculations of strongly correlated states of spin defects in diamond. Within this theory, effective Hamiltonians are constructed, which can be solved by classical and quantum computers; the latter promise a much more favorable scaling as a function of system size than the former. In particular, we report a study of the neutral group-IV vacancy complexes in diamond, and we discuss their strongly-correlated spin-singlet and spin-triplet excited states. Our results provide valuable predictions for experiments aimed at optical manipulation of these defects for quantum information technology applications.