Tuning the magnetic ordering driven by cationic antisite defects in the Li(ZnMn)As system

The electronic structure and magnetic properties of Li(ZnMn)As with antisite defects have been investigated by using first-principles calculations within the Perdew-Burke-Ernzerhof generalized gradient approximation. The cation antisite defect induced by Zn substitution for As was considered. Mn-3d, As-4p, Zn-4s, and Zn-4p were involved in the formation of d-sp hybrid orbitals, which enhanced the non-localized properties of Mn-3d electrons and provided a channel of Mn(?)-As(?)-ZnAs(?)-Mn(?) for indirect exchange of electrons between the magnetic ions. The antisite defect of Zn-substituted As belonged to the acceptor doping, rendering the compound p-type characteristics. The existence of the extra free hole carriers regulated the magnetic ordering transition. The ferromagnetic coupling between the Mn magnetic dopants was more favorable in the system with an antisite defect. In this paper, a novel type of dilute magnetic semiconductor with controllable carriers was designed and the mechanism of ferromagnetic coupling was revealed, which provided a theoretical reference for the subsequent studies.

Automated summary

The electronic structure and magnetic properties of Li(ZnMn)As with antisite defects were investigated using first-principles calculations. The cation antisite defect induced by Zn substitution for As was considered. The formation of d-sp hybrid orbitals involving Mn-3d, As-4p, Zn-4s, and Zn-4p enhanced the non-localized properties of Mn-3d electrons and provided a channel for indirect exchange of electrons between the magnetic ions. The antisite defect of Zn-substituted As acted as an acceptor doping, resulting in p-type characteristics and regulating the magnetic ordering transition. The ferromagnetic coupling between the Mn magnetic dopants was favored in the system with an antisite defect. This study designed a novel type of dilute magnetic semiconductor with controllable carriers and revealed the mechanism of ferromagnetic coupling, providing a theoretical reference for future studies.