https://doi.org/10.1140/epjd/e2005-00221-7
Phase separation of ferromagnetic spin-1 Bose gases in non-zero magnetic field
1
Research Group for Statistical Physics of the Hungarian Academy of Sciences,
Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
2
Department of Physics of Complex Systems, Roland Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
3
Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, 1525 Budapest, Hungary
Corresponding author: a szirmai@complex.elte.hu
Received:
28
February
2005
Revised:
31
May
2005
Published online:
9
August
2005
Properties of ferromagnetic spin-1 Bose gases above and at the temperature of Bose-Einstein condensation are studied in the presence of a magnetic field. The equation of state is given in a mean-field approximation. It is found that there exists a critical magnetic field and below that two phases coexist with different particle densities. The stability of the system is also investigated with the help of the susceptibility matrix. The dynamics of the system is worked out in the Random Phase Approximation and the soft mode corresponding to the critical point is given.
PACS: 03.75.Mn – Multicomponent condensates; spinor condensates / 03.75.Hh – Static properties of condensates; thermodynamical, statistical and structural properties / 67.40.Db – Quantum statistical theory; ground state, elementary excitations
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005
