Field-induced magnetic structures in the chiral polar antiferromagnet Ni2InSbO6

We have performed 115In-NMR spectroscopy for Ni2InSbO6 with corundum-related crystal structure to reveal magnetic structures that develop in high magnetic fields. At low fields Ni2InSbO6 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 115In-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 a magnetic field that modifies the magnetic structure of an antiferromagnetic chiral magnet.