Detection of sub-lattice magnetism in sigma-phase Fe-V compounds by zero-field NMR

TL;DR

This study uses zero-field NMR to detect sub-lattice magnetism in sigma-phase Fe-V alloys, revealing site-dependent magnetic properties and a correlation between V and Fe magnetic moments.

Contribution

First successful zero-field NMR detection of sub-lattice magnetism in sigma-phase Fe-V alloys, showing site-specific magnetic behavior and induced magnetism in V atoms.

Findings

Vanadium atoms are magnetic on all five crystallographic sites.

Magnetic moments vary with composition and site, strongest at site A.

V magnetic moments are linearly correlated with Fe moments.

Abstract

The first successful measurements of a sub-lattice magnetism with 51V NMR techniques in the sigma-phase Fe(100-x)Vx alloys with x = 34.4, 39.9 and 47.9 are reported. Vanadium atoms present on all five crystallographic sites are magnetic. Their magnetic properties are characteristic of a given site, which strongly depend on the composition. The strongest magnetism exhibit sites A and the weakest one sites D. The estimated average magnetic moment per V atom decreases from 0.36 muB for x = 34.4 to 0.20 muB for x = 47.9. The magnetism revealed at V atoms is linearly correlated with the magnetic moment of Fe atoms, which implies that the former is induced by the latter.