Photoemission spectra of LaMnO3 controlled by orbital excitations
We investigate the spectral function of a hole moving in the orbital-ordered ferromagnetic planes of LaMnO3, and show that it depends critically on the type of orbital ordering. While the hole does not couple to the spin excitations, it interacts strongly with the excitations of e(g) orbitals (orbitons), leading to a new type of quasiparticle with a dispersion on the orbiton energy scale and with strongly enhanced mass and reduced weight. Therefore we predict a large redistribution of spectral weight with respect to the bands found in local density approximation (LDA) or in LDA+U.
van Den Brink J
Max-Planck-Institut fur Festkorperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany and Faculty of Applied Physics and Mesa+ Institute, University of Twente, Box 217, NL-7500 AE Enschede, The Netherlands.
Horsch
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Oles
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