Field-induced magnetic structures in the chiral polar antiferromagnet Ni$_2$InSbO$_6$

TL;DR

This study uses high-field $^{115}$In-NMR spectroscopy to investigate magnetic structures in Ni$_2$InSbO$_6$, revealing field-induced transitions from helical to canted antiferromagnetic states influenced by the crystal's chirality and polarity.

Contribution

First microscopic analysis of high-field magnetic structures in Ni$_2$InSbO$_6$, demonstrating field-induced magnetic state transitions in a chiral polar antiferromagnet.

Findings

Helical magnetic order at low fields.

Canted antiferromagnetic structure in high fields.

Propagation vector rotation depends on field direction.

Abstract

We have performed $^{115}$In-NMR spectroscopy for Ni$_{2}$InSbO$_6$ with corundum-related crystal structure to reveal magnetic structures that develop in high magnetic fields. At low fields Ni$_{2}$InSbO$_6$ shows a helical magnetic order with a long wavelength because of its chiral and polar crystal structure. The field-induced magnetic state was not investigated by microscopic experiment because an extremely high magnetic field is required to modify the antiferromagnetically coupled helical structure. From the analysis of our $^{115}$In-NMR spectra obtained at high magnetic fields, we confirm that the canted antiferromagnetic structure appears in fields applied in the $[110]$ direction and the propagation vector of magnetic helix is rotated toward the field direction for fields in the $[001]$ direction. We discuss the effect of magnetic field that modifies the magnetic structure of an antiferromagnetic chiral magnet.