Low Temperature Physics: 33, 965 (2007); https://doi.org/10.1063/1.2747074 (9 pages)
Fizika Nizkikh Temperatur: Volume 33, Number 11 (November 2007), p. 1271-1281 ( to contents , go back )
Classification of equilibrium states of magnets with vector and quadrupole order parameters
Karazin Kharkov National University, 4, Svobody Sq., Kharkov 61077, Ukraine
National Science Center «Kharkov Institute of Physics and Technology», 1 Akademicheskaya Str., Kharkov 61108, Ukraine
Белгородский государственный университет, ул. Победы, 85, г. Белгород, 308015, Россия
Received May 31, 2007
The classification of equilibrium states of magnetic condensed media, the symmetry of which is spontaneously broken relative to rotations in the spin space and translations in the configuration space, is carried out. The cases of vector and tensor order parameters are considered. The conditions of an unbroken symmetry and a spatial symmetry of the equilibrium states is formulated. The connection of these symmetry conditions with ferromagnetic, antiferromagnetic, ferrimagnetic and spiral magnetic states is found out for the case of vector order parameter. The connection of the above symmetry conditions with quadrupole magnetic states — uniaxial and biaxial magnetic nematics, magnetic cholesterics and dual spiral magnetic — is established.
PACS. 75.40.Cx Static properties (order parameter, static susceptibility, heat capacities, critical exponents,etc)
Key words: magnets, phase conversions, order parameter, quasiaverages, symmetry, Gibbs distribution, spin nematic.