Magnetic structure and domain conversion of quasi-2D frustrated antiferromagnet CuCrO2 probed by NMR

TL;DR

This study uses NMR to investigate the magnetic structure and domain behavior of CuCrO2, revealing field-induced spin reorientation and domain conversion in a quasi-2D frustrated antiferromagnet.

Contribution

It provides the first direct observation of spin plane reorientation and domain conversion in CuCrO2 under magnetic fields using NMR spectroscopy.

Findings

Reorientation of spin plane observed during magnetic field rotation.

Quantitative analysis of domain conversion between different magnetic states.

High-field effects suggest influence on interplanar magnetic ordering.

Abstract

We have carried out 63,65Cu NMR spectra measurements in magnetic field up to about 15.5 T on single crystal of a multiferroic triangular-lattice antiferromagnet CuCrO2. The measurements were performed for perpendicular and parallel orientation of the magnetic field with respect to the c-axis of the crystal, and the detailed angle dependence of the spectra on the magnetic field direction within ab-plane was studied. The shape of the spectra can be well described in the model of spiral spin structure proposed by recent neutron diffraction experiments. When field is rotated perpendicular to crystal c-axis, we observed, directly for the first time, a remarkable reorientation of spin plane simultaneous with rotation of the incommensurate wavevector by quantitatively deducing the conversion of less energetically favorable domain to a more favorable one. At high enough fields parallel to c-axis, the data are consistent with either a field-induced commensurate spiral magnetic structure or an incommensurate spiral magnetic structure with a disorder in the c direction, suggesting that high fields may have influence on interplanar ordering.