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arXiv · 0901.2650

The Fermi surface and the role of electronic correlations in Sm$_{2-x}$Ce$_{x}$CuO$_4$

M. M. Korshunov·E. V. Zakharova·I. A. Nekrasov·Z. V. Pchelkina·S. G. Ovchinnikov
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Abstract

Using LDA+GTB (local density approximation+generalized tight-binding) hybrid scheme we investigate the band structure of the electron-doped high-$T_c$ material Sm$_{2-x}$Ce$_{x}$CuO$_4$. Parameters of the minimal tight-binding model for this system (the so-called 3-band Emery model) were obtained within the NMTO ($N$-th order Muffin-Tin orbital) method. Doping evolution of the dispersion and Fermi surface in the presence of electronic correlations was investigated in two regimes of magnetic order: short-range (spin-liquid) and long-range (antiferromagnetic metal). Each regime is characterized by the specific topologies of the Fermi surfaces and we discuss their relation to recent experimental data.

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M. M. Korshunov, E. V. Zakharova, I. A. Nekrasov, Z. V. Pchelkina, S. G. Ovchinnikov. 2009-12-03. The Fermi surface and the role of electronic correlations in Sm$_{2-x}$Ce$_{x}$CuO$_4$. https://doi.org/10.1088/0953-8984%2F22%2F1%2F015701

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