https://doi.org/10.1140/epjb/e2002-00405-5
Interplay of charge, spin, orbital and lattice correlations in colossal magnetoresistance manganites
1
Physikalisches Institut, Universität Bayreuth, 95440
Bayreuth, Germany
2
Institut für Physik, Ernst-Moritz-Arndt Universität
Greifswald, 17487 Greifswald, Germany
Corresponding author: a Alexander.Weisse@uni-bayreuth.de
Received:
4
September
2002
Revised:
8
November
2002
Published online:
31
December
2002
We derive a realistic microscopic model for doped colossal
magnetoresistance manganites, which includes the dynamics of charge,
spin, orbital and lattice degrees of freedom on a quantum mechanical
level. The model respects the SU(2) spin symmetry and the full
multiplet structure of the manganese ions within the cubic lattice.
Concentrating on the hole doped domain () we study
the influence of the electron-lattice interaction on spin and
orbital correlations by means of exact diagonalisation techniques.
We find that the lattice can cause a considerable suppression of the
coupling between spin and orbital degrees of freedom and show how
changes in the magnetic correlations are reflected in dynamic phonon
correlations. In addition, our calculation gives detailed insights
into orbital correlations and demonstrates the possibility of
complex orbital states.
PACS: 71.10.-w – Theories and models of many-electron systems / 71.38.-k – Polarons and electron-phonon interactions / 75.30.Vn – Colossal magnetoresistance
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002