Spin-polarized cation monovacancies in wurtzite structure semiconductors: first-principles study

Abstract

We study spin-polarized cation vacancies in wurtzite structure semiconductors (BeO, ZnO, ZnS, CdS, BN, AlN, GaN and GaP) by using first-principles calculations based on the density functional theory. We find that C3v geometries are the most stable and are spin-polarized. Two majority spin electrons occupying the defect E level lead to the magnetic moment of 2 μB in the case of II–VI semiconductors. On the contrary, in the case of III–V semiconductors, three majority spin electrons occupying the defect E and A1 levels induce the magnetic moment of 3 μB. The spin polarization of cation vacancies in oxides and nitrides are found to be stable compared with other cation vacancies in II–VI and III–V semiconductors, respectively. We clarify that the effect of the symmetry lowering from C3v to Cs is small and thus confirm that the spin polarized C3v geometries are the most stable.

Electronic structures of puckered bilayer group-V two-dimensional materials: group theoretical analysis

“…33) In this study, we adopt the Mulliken and Bethe symbols for the IR in most cases. 19,[30][31][32]34,35) However, in some exceptional cases, IR do not correspond to conventional IR as mentioned in the next section. In this nonconventional case, we use other symbols.…”

“…The projection operator method is used for this identification, which was explained in previous papers. 19,[30][31][32] This method is implemented in the first-principles calculation code, PHASE/0, and thus IR are identified automatically by using computers. 33) In this study, we adopt the Mulliken and Bethe symbols for the IR in most cases.…”

Analysis of band structures of phosphorene and bismuthene based on the double group theory

“…The function of identifying IR was implemented in some first-principles codes. [25][26][27][28][29] We also reported methods for the non-SOC calculations [30][31][32][33][34] and for the SOC calculations on symmorphic systems. 35) We here report the method for nonsymmorphic systems.…”