Effect of Absorbed Hydrogen on Magnetic Properties of Mn2fesi Inverse Heusler Alloy

Abstract

A study of hydrogen absorption in Mn2FeSi half-metal inverse Heusler alloy and the effect of hydrogen on its magnetic properties was carried out. A pristine Mn2FeSi alloy prepared by arc melting consists of matrix with the inverse Heusler XA structure and second phase particles with the β-Mn type cubic structure. The phase with the XA structure is antiferromagnetic with the Néel temperature around 50 K while the phase with the β-Mn type structure is ferrimagnetic. Hydrogen is absorbed preferentially in the β-Mn type phase and suppresses ferrimagnetic ordering of spins. As a consequence hydrogen-loaded Mn2FeSi sample exhibits purely antiferromagnetic behaviour. This result shows that magnetic properties of Heusler alloys can be modified by hydrogen treatment.

Keywords: heusler alloy, hydrogen absorpttion, anti-ferromagnetism