FeSi: Experimental realization of an antiferromagnetic inverse-Heusler alloy*

Search for low-moment magnetic materials with high spin-polarization is important for future spintronics applications. In this work, we have conducted detailed and varied materials growth and characterization along with complementary first-principles calculations to investigate the structure and magnetism of Mn₂FeSi, which is a prospective inverse-Heusler material identified by prior calculations. We show that Mn₂FeSi adopts a cubic structure that is in very good agreement with theoretical estimates while the magnetic and resistivity measurements show behavior consistent with antiferromagnetism which can be tuned to a very low-moment state under appropriate growth conditions. Supporting first-principles calculations show that compensated antiferromagnetic states are energetically feasible. Our work provides new evidence that the magnetic properties of Manganese-based inverse-Heuslers can be useful to explore new applications in the area of spintronics.