Magnetic Orderings and Phase Separations in the Zero-Bandwidth Limit of the Extended Hubbard Model with Intersite Magnetic Interactions

• Authors: W. Kłobus , K. Kapcia , S. Robaszkiewicz
• Languages of publication: EN

Abstracts

EN

A simple effective model for a description of magnetically ordered insulators is analysed. The tight binding Hamiltonian consists of the effective on-site interaction (U) and intersite magnetic exchange interactions (J^{z}, J^{xy}) between nearest neighbours. The phase diagrams of this model have been determined within the variational approach, which treats the on-site interaction term exactly and the intersite interactions within the mean-field approximation. We show that, depending on the values of interaction parameters and the electron concentration, the system can exhibit not only homogeneous phases: (anti-)ferromagnetic (F_α) and nonordered (NO), but also phase separated states (PS_α: F_α-NO).

Keywords

EN

71.10.Fd; 75.10.-b; 75.30.Gw; 64.75.Gh; 71.10.Hf

Discipline

• 75.30.Gw: Magnetic anisotropy
• 71.10.Fd: Lattice fermion models (Hubbard model, etc.)
• 75.10.-b: General theory and models of magnetic ordering(see also 05.50.+q Lattice theory and statistics)
• 71.10.Hf: Non-Fermi-liquid ground states, electron phase diagrams and phase transitions in model systems
• 64.75.Gh: Phase separation and segregation in model systems (hard spheres, Lennard-Jones, etc.)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2010
• Volume: 118
• Issue: 2
• Pages: 353-355

Dates

published

2010-08

Contributors

author

W. Kłobus

• Electron States of Solids Division, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

author

K. Kapcia

• Electron States of Solids Division, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

author

S. Robaszkiewicz

• Electron States of Solids Division, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

References

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Identifiers

DOI

10.12693/APhysPolA.118.353