ON THE HYDRODYNAMIC THEORY OF A MAGNETIC LIQUID .2. HYDRODYNAMIC MODES IN THE HEISENBERG FLUID

Authors
Citation
Im. Mryglod et R. Folk, ON THE HYDRODYNAMIC THEORY OF A MAGNETIC LIQUID .2. HYDRODYNAMIC MODES IN THE HEISENBERG FLUID, Physica. A, 234(1-2), 1996, pp. 129-150
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
ISSN journal
0378-4371
Volume
234
Issue
1-2
Year of publication
1996
Pages
129 - 150
Database
ISI
SICI code
0378-4371(1996)234:1-2<129:OTHTOA>2.0.ZU;2-0
Abstract
On the basis of our previous results (Physica A 220 (1995) 325) the co llective mode spectrum of the Heisenberg ferrofluid model is studied i n the hydrodynamic region. We start from the rigorous microscopic appr oach taking into account all conserved quantities and calculate the ex plicit expressions for the dispersion and damping coefficient of sound modes. It is shown that the sound velocity of Heisenberg ferrofluid a t constant external magnetic held is isotropic and can be expressed by the adiabatic compressibility at constant magnetization m. We also ca lculate the heat and spin modes which are purely diffusive. Explicit e xpressions for the viscosity, thermal conductivity, spin diffusion and thermomagnetic diffusion coefficients containing time correlation fun ctions are derived. Our results are compared with previous ones obtain ed mainly within phenomenological theories.