Evidence of magnetoelastic coupling and magnetic phase coexistence in Mn$_{1.7}$Fe$_{1.3}$Si Heusler Alloy

TL;DR

This study reveals magnetoelastic coupling and magnetic phase coexistence in Mn$_{1.7}$Fe$_{1.3}$Si Heusler alloy, highlighting complex magnetic transitions and potential spintronic applications.

Contribution

It provides a comprehensive analysis of structural, magnetic, and transport properties, uncovering magnetoelastic effects and canted antiferromagnetic order in this Heusler compound.

Findings

Paramagnetic to ferromagnetic transition at 85 K

Magnetoelastic coupling evidenced by volume change

Field-induced metamagnetic transition at low temperatures

Abstract

Noncollinear metallic antiferromagnets, with their rapid spin dynamics, efficient spin transport, and distinctive spin textures, play a pivotal role in advancing the field of spintronics. In this study, we report a comprehensive investigation of the structural, magnetic, and transport properties of cubic Mn$_{1.7}$Fe$_{1.3}$Si Heusler compound. Temperature-dependent magnetization measurement reveals a paramagnetic to ferromagnetic transition at $T_C$ = 85 K, followed by a spin reorientation transition. Neutron diffraction data, analyzed as a function of temperature, demonstrates that the occurrence of a spin-reorientation transition is accompanied by magnetoelastic coupling, as evidenced by a change in unit cell volume below $T_C$. Magnetic structure refinement of the low-temperature neutron powder diffraction data confirms the canted antiferromagnetic ordering below 55 K. The metallic nature of the sample is confirmed by the gradual decrease in the $\rho$(T) with decreasing temperature. At low temperatures, a field-induced metamgnetic transition is observed in both, magnetization and magneto-transport measurements. The $H-T$ phase diagram shows a phase-coexistence region emerging at low temperatures for H $<$ 2.5 T. These findings provide valuable insights into the magnetic and transport behavior of the Heusler compounds, underscoring their potential for spintronic applications.