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AM Oles

Publications and source records attributed to AM Oles.

At least 19 recordsLinked to original sources
PubMed2000

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.

Journal Article↗
PubMed2000

One-dimensional metallic behavior of the stripe phase in La2-xSrxCuO4

Using an exact diagonalization method within the dynamical mean-field theory we found stable stripe phases in the two-dimensional Hubbard model doped by 0.03<delta<0.2 holes, with a crossover from diagonal to vertical site-centered stripes at doping delta approximately 0.05. The doping dependence of the size of magnetic domains and chemical potential shift Delta&mgr; approximately -delta(2) are in quantitative agreement with the experimental results for La2-xSrxCuO4. The one-dimensional metallic behavior along the domain walls explains the observed suppression of spectral weight along the Brillouin zone diagonal.

Journal Article↗