Temperature effects in a spin-orbital model for manganites (2006)
Daghofer, M., Neuber, D. R., Oleś, A. M., Von Der Linden, W.
We study a two-dimensional effective orbital superexchange model derived for strongly correlated e,, electrons coupled to t(2g) core spins in layered manganites. One finds that the ferromagnetic (FM)...
Microscopic theory of magnetic interactions in KCuF3 and LaMnO3 – The role of charge transfer (2006)
Oleś, A. M., Feiner, L. F., Horsch, P., Khaliullin, G.
We analyze the spin exchange interactions J(ab) and J(c) in the A-type anti ferromagnetic phase of KCuF3 and LaMnO3. One finds that the quasi one-dimensional spin interactions in KCuF3 are consistent...
Doping dependence of spin and orbital correlations in layered manganites (2006)
Daghofer, M., Oleś, A. M., Neuber, D. R., Von Der Linden, W.
We investigate the interplay between spin and orbital correlations in monolayer and bilayer manganites using an effective spin-orbital t-J model which treats explicitly the e(g) orbital degrees of...
Spin-orbital entanglement and violation of the Goodenough-Kanamori rules (2006)
Oleś, A. M., Horsch, P., Feiner, L. F., Khaliullin, G.
We point out that large composite spin-orbital fluctuations in Mott insulators with t(2g) orbital degeneracy are a manifestation of quantum entanglement of spin and orbital variables. This results in...
Metoki, N., Kaneko, K., Raymond, S., Sanchez, J.-P., Piekarz, P., Parlinski, K., ...
Influence of local electron interactions on phonon spectrum in iron (2006)
Lazewski, J., Piekarz, P., Oleś, A. M., Parlinski, K.
The density functional generalized-gradient approximation with the local Coulomb interaction U and the direct method have been applied to study the electronic structure and the phonon spectrum of Fe...
Mechanism of the Verwey transition in magnetite (2006)
Piekarz, P., Parlinski, K., Oleś, A. M.
By combining ab initio results for the electronic structure and phonon spectrum with the group theory, we establish the origin of the Verwey transition in Fe3O4. Two primary order parameters with X-3...
Onset of metallic ferromagnetism in a doped spin-orbital chain (2005)
Daghofer, M., Oleś, A. M., Von Der Linden, W.
First-principles study of phonon modes in PuCoGa5 superconductor (2005)
Piekarz, P., Parlinski, K., Jochym, P. T., Oleś, A. M., Sanchez, J. P., Rebizant, J.
On the nature of the magnetic transition in a Mott insulator (2004)
Fleck, M., Lichtenstein, A. I., Zacher, M. G., Hanke, W., Oleś, A. M.
Using a combination of exact enumeration and the dynamical mean-field theory (DMFT) we study the drastic change of the spectral properties, obtained in the half-filled two-dimensional Hubbard model...
Spin and orbital correlations in spin orbital models for t2g orbitals (2004)
Oleś, A. M., Horsch, P., Khaliullin, G.
We use exact diagonalization of four-site chains to demonstrate the effects of Hund's exchange and spin-orbit coupling on the intersite spin and orbital correlations in t(2g) systems. Except for...
Origin of the optical gap in half-doped manganites (2002)
Cuoco, M., Noce, C., Oleś, A. M.
We have analyzed the coexisting charge and orbital ordering in half-doped manganites using a model which includes Coulomb and Jahn-Teller orbital polarization interactions. Most surprisingly, the gap...
Orbital polarons in LaMnO3 (2002)
Bała, J., Oleś, A. M., Horsch, P.
We investigate the spectral functions and orbital correlation functions relative to the position of an e,. hole moving in the ferromagnetic plane of orbitally ordered LaMnO3. Polarization of orbitals...
Orbital-lattice polarons in ferromagnetic LaMnO3 (2002)
Bała, J., Oleś, A. M., Sawatzky, G. A.
We investigate the combined influence of superexchange and electron-phonon interactions on the excitation spectra and on hole propagation in a ferromagnetic plane of LaMnO3. The Jahn- Teller effect...
Quasiparticles and the structure of orbital polarons in ferromagnetic LaMnO3 (2002)
Bała, J., Oleś, A. M., Horsch, P.
We investigate the spectral functions and orbital-correlation functions relative to the position of an e(g) hole moving in the ferromagnetic plane of orbitally ordered LaMnO3. Solving this problem in...
Photoemission spectra of LaMnO3 controlled by orbital excitations (2000)
Van Den Brink, J., Horsch, P., Oleś, A. M.
Quasiparticle broadening in insulating copper oxides. (1999)
Fleck, M., Van Den Brink, J., Lichtenstein, A. I., Oleś, A. M., Hedin, L.
Orbital dynamics in ferromagnetic transition-metal oxides. (1999)
Van Den Brink, J., Horsch, P., Mack, F., Oleś, A. M.
Orbitons in ferromagnetic insulating manganites. (1999)
Van Den Brink, J., Horsch, P., Mack, F., Oleś, A. M.
Dynamical mean-field theory for doped antiferromagnets. (1998)
Fleck, M., Liechtenstein, A. I., Oleś, A. M., Hedin, L., Anisimov, V. I.