Hyperfine structure of transition metal defects in SiC

Transition metal (TM) defects in silicon carbide (SiC) are a promising platform quantum technology, especially because some TM emit the telecom band. We develop theory for interaction of an active electron $D$-shell defect SiC with nuclear spin and derive effective hyperfine tensor within Kramers doublets formed by spin-orbit coupling. Based on our we discuss possibility to exchange states potential applications manipulation long-lived nunclear-spin based memories.