Fig. 1
From: Ab initio description of highly correlated states in defects for realizing quantum bits
Defects for quantum computing. a Nitrogen-vacancy center in diamond. b Divacancy in SiC. The position of vacancies is depicted by a small dots. The C3 symmetry axis of the C3v symmetry is also shown. The spin density is localized on the carbon dangling bonds (pink lobes) in both defects. We show the hh configuration of divacancy in 4H polytype of SiC (see Supplementary Information for more details about the 4H polytype and the different divacancy configurations). The schematic diagram of the calculated spinpolarized DFT Kohn–Sham levels in the band gap is depicted for c NV center and d divacancy. The double lines for the e levels represent the double degenerate {e x , e y } states that can be occupied by two electrons in each spin channel. The a state transforms as a1 in C3v symmetry. The subscripts text of these labels represents the localization of the dangling bonds, i.e., C orbitals or Si orbitals. The eSi orbitals do not contribute to the qubit operation of the defect and can be ignored in the context. The similarity in the electronic structure of the two defects is apparent. VB and CB represent valence and conduction bands, respectively
