Electronic and magnetic properties of 3d transition-metal-doped Ⅱ-Ⅳ-Ⅴ22 chalcopyrite semiconductor

Abstract

A systematic study based on ab initio calculation within local spin density appr oximation is carried out for material design of Ⅱ-Ⅳ-Ⅴ22 chal copyrite semiconductor (CdGeP22 and ZnGeP22) doped with 3d-TM (TM= V, Cr, Mn, Fe, Co and Ni). It is found that the ferromagnetic (FM) state will be realized in V and Cr doped CdGeP22 and ZnGeP22; for Mn, Fe and Co doped ones, the antiferromagnetic (AFM) states are more stable than FM states; whereas dope d with Ni, the dilute magnetic semiconductor (DMS) shows unstable ferromagnetism . It is suggested that Ⅰ-Ⅳ-Ⅴ22 chalcopyrite semiconductor doped with Cr is a candidate for high Curie temperature (TCC) DMS. When th e t2g2g states of TM are partially occupied, the DMS doped with TMs shows a stable FM state, whereas when the t2g2g states of TMs are fully occupied or empty, the DMS with the TM shows AFM state. In order to elucid ate the underlying mechanism of the ferromagnetism in DMS, the magnetism in (C d,Mn)GeP22 and (Cd,Mn)GeP22 under the carrier (elect ron or hole) doping treatment is investigated. It is found that it is crucial to realize the carrier-induced ferromagnetism, indopendent of whethe r the doped carrier has itinerant TM-3d character or not.