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arXiv · 1310.7680

Pressure effect on the energy structure and superexchange interaction of the undoped orthorhombic La2CuO4: beyond the low-energy approximation

Vladimir A. Gavrichkov·Zlata V. Pchelkina·Igor A. Nekrasov·Sergey G. Ovchinnikov
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Abstract

Using LDA+GTB multi-band approach, we studied the compression dependence of the electronic structure and in-plane superexchange interaction J(P) in the antiferromagnetic La214 at the 0% and 3% - hydrostatic and unaxial (along c axial) compression. We obtained the superexchange interaction J(P=0)~0.15eV is enhanced by ~20% under the 3% - hydrostatic compression and vice versa the J(P) is decreased slightly by ~5,7% under the 3% - uniaxial compression. In both cases the J(P) correlates with the in-plane hopping parameters and dd-excitation energy δ_s=e(^3B_{1})-e(A_{1})$ involving the the two-hole states: Zhang-Rice singlet and ^3{B_{1}} triplet states. The spectral density of the first removal states is a combined singlet-triplet character and a sign of changes in the one with the pressure clearly reproduces the \vec{k}-distribution of quasiparticle states with a different a_1- and b_1-symmetry over the Brillouin zone as a whole.

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Vladimir A. Gavrichkov, Zlata V. Pchelkina, Igor A. Nekrasov, Sergey G. Ovchinnikov. 2013-10-29. Pressure effect on the energy structure and superexchange interaction of the undoped orthorhombic La2CuO4: beyond the low-energy approximation. https://arxiv.org/abs/1310.7680

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