First-principles study of magnetic properties of ultra-thin MoSi2 films

The magnetic properties of ultra-thin tetragonal MoSi2 thin films were investigated by the first-principles method. Our results indicate that the Si terminated MoSi2 film is always metallic independent of its thickness and non-magnetic when its thickness is larger than three atomic layers. However, the three-atomic-layer MoSi2 film (1L MoSi2) exhibits magnetism with magnetic moments of similar to 0.274 mu(B)/atom for Mo atoms and similar to 0.096 mu(B)/atom for Si atoms. The system shows weaker magnetism with magnetic moments of similar to 0.184 mu(B)/atom for Mo and similar to 0.079 mu(B)/atom for Si after unilateral surface hydrogenation and becomes non-magnetic after bilateral hydrogenation. By comparing the ferromagnetic (FM) configuration with antiferromagnetic configurations, we found that the FM order is the ground state with the lowest energy. Furthermore, it is found that the magnetic properties of 1L MoSi2 can be tuned effectively by strain. Published by AIP Publishing.