First-principles study of the magnetic and electronic properties of AMnAs (A=Li, Na, K, Rb, Cs)

• The magnetic and electronic properties of AMnAs (A=Li, Na, K, Rb, Cs) are investigated.
• The relative energetic ordering of various magnetic phases is obtained within both GGA and LDA.
• Our calculations predict that all AMnAs are semiconductors.

Recent studies have demonstrated that antiferromagnetic (AFM) semiconductors are promising alternative materials for spintronic applications. In this work, we report a detailed investigation of the magnetic and electronic properties of AMnAs (A=Li, Na, K, Rb, Cs) using density functional theory. It is found that all studied compounds are ordered antiferromagnetically in the MnAs ab plane, however, along the c axis, NaMnAs is ordered ferromagnetically which is different from the AFM coupling of other materials. These results on magnetic structures are in good agreement with observed facts. Furthermore, our calculations predict that all materials have a semiconducting band structure, which indicates the potential of device applications.