Magnetic mechanism investigations on n-type ferromagnetic Li(Zn,Mn)As

•The origination of magnetism in n-type Li(Zn,Mn)As system was investigated.•Ferromagnetism is found to be the preferred ground state.•Mn-3d states are observed to hybridize strongly with the As-2p and Li-1s states around Fermi level.•The sp–d exchange mechanism are suggested to dominate the n-type Li(Zn,Mn)As magnetic semiconductors system.

First-principles density-functional theory calculations were performed to study the origination of magnetism in n-type Li(Zn,Mn)As system. The formation energies of n-type defects are negative and the system becomes spin polarized when Li-interstitial is introduced. The energy difference between ferromagnetic and antiferromagnetic coupling of Mn atoms indicate that ferromagnetism is the preferred ground state. The atomic magnetic moments mainly come from Mn, Li and As atoms. The Mn-3d states are observed to hybridize strongly with the As-4p and Li-2s states around Fermi level. Based on the calculations, sp–d hybridization mechanism is suggested to be responsible for the ferromagnetic coupling of n-type Li(Zn,Mn)As.