Interplay between charge and magnetic orderings in the zero-bandwidth limit of the extended Hubbard model for strong on-site repulsion
Loading...
Date
2012-06
Advisor
Editor
Journal Title
Journal ISSN
Volume Title
Publisher
Polish Academy of Sciences, Institute of Physics, al. Lotników 32-46, Pl-02-668 Warsaw, Poland
Title alternative
Abstract
A simple effective model of charge ordered and (or) magnetically ordered insulators is studied. The tight binding Hamiltonian analyzed consists of (i) the effective on-site interaction U, (ii) the intersite density-density interaction W and (iii) intersite magnetic exchange interaction Jz (or Jxy) between nearest-neighbors. The intersite interaction are treated within the mean-field approximation. One shows that the systems considered can exhibit very interesting multicritical behaviors, including among others bicritical, tricritical, tetracritical and critical end points. The analysis of the model has been performed for an arbitrary electron concentration as well as an arbitrary chemical potential in the limit of strong on-site repulsion. The phase diagrams obtained in such a case are shown to consist of at least 9 different states, including four homogenous phases: nonordered (NO), ferromagnetic (F), charge ordered (CO), ferrimagnetic (intermediate, I) and five types of phase separation: NO-NO, F-NO, F-F, CO-F, CO-I.
Description
This is an author-created, un-copyedited version of an article accepted for publication in Acta Physica Polonica A.
The Version of Record is available online at http://przyrbwn.icm.edu.pl/APP/PDF/121/a121z5p12.pdf
Sponsor
National Science Center (NCN) as a research project in years 2011-2013, under grant No. DEC-2011/01/N/ST3/00413;
European Commission and Ministry of Science and Higher Education (Poland) - partial financial support from European Social Fund – Operational Programme "Human Capital" – POKL.04.01.01-00-133/09-00 – "Proinnowacyjne kształcenie, kompetentna kadra, absolwenci przyszłości".
Keywords
charge orderings, magnetic orderings, extended Hubbard model, atomic limit, phase separation
Citation
Acta Physica Polonica A, Vol. 121, No. 5-6, 1032-1034 (2012)
Seria
ISBN
ISSN
0587-4246