We have carried out 63,65Cu NMR spectra measurements in magnetic field up to about 45~T on single crystal of a multiferroic triangular antiferromagnet CuCrO2. The measurements were performed for magnetic fields aligned along the crystal c-axis. Field and temperature evolution of the spectral shape demonstrates a number of phase transitions. It was found that the 3D magnetic ordering takes place in the low field range (H≲15~T). At higher fields magnetic structures form within individual triangular planes whereas the spin directions of the magnetic ions from neighboring planes are not correlated. It is established that the 2D-3D transition is hysteretic in field and temperature. Lineshape analysis reveals several possible magnetic structures existing within individual planes for different phases of CuCrO2. Within certain regions on the magnetic H-T phase diagram of CuCrO2 a 3D magnetic ordering with tensor order parameter is expected.
@article{arxiv.1607.02765,
title = {Magnetic phases of quasi-two-dimensional antiferromagnet on triangular lattice CuCrO$_2$},
author = {Yu. A. Sakhratov and L. E. Svistov and P. L. Kuhns and H. D. Zhou and A. P. Reyes},
journal= {arXiv preprint arXiv:1607.02765},
year = {2016}
}