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Photoemission spectra of LaMnO3 controlled by orbital excitations

Jeroen van den Brink·Peter Horsch·Andrzej M. Oles
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Abstract

We investigate the spectral function of a hole moving in the orbital-ordered ferromagnetic planes of LaMnO$_3$, 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 new type of quasiparticles 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.

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Jeroen van den Brink, Peter Horsch, Andrzej M. Oles. 2001-04-25. Photoemission spectra of LaMnO3 controlled by orbital excitations. https://doi.org/10.1103/physrevlett.85.5174

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