Stability and Molecular Pathways to The Formation of Spin Defects in Wide Band Gap Semiconductors for Quantum Technologies

Spin defects in wide-bandgap semiconductors provide a promising platform to create qubits for quantum technologies. Their synthesis, however, presents considerable challenges, and the mechanisms responsible for their generation or annihilation are poorly understood. Here, we elucidate spin defect formation processes in a solid-state crystals for leading qubit candidates—the divacancy complex in silicon carbide [1] and the nitrogen vacancy (NV) center in diamond. Using <i>ab initio</i> molecular dynamics with enhanced sampling techniques, we characterize the formation mechanism of spin defects. We then predict the conditions favoring the formation of spin defects over the competing process of other undesirable defects. Moreover, we identify pathways to create new spin defects and determine their electronic properties using hybrid density functional calculations. The detailed view of the mechanisms that underpin the formation and dynamics of spin defects presented here may facilitate the realization of qubits for designing room temperature quantum devices.<br/><br/>[1] E. M.Y. Lee, A. Yu, J. J. de Pablo, and G. Galli. <i>Nature Communications, </i><b>12</b>, <i>6325</i> (2021)