Dominance of many-body effects over one-electron mechanism for band structure doping dependence in Nd${}_{2-x}$Ce${}_x$CuO${}_4$: LDA+GTB approach

Abstract

In the present work we report the band structure calculations for the high temperature superconductor Nd${}_{2-x}$Ce${}_x$CuO${}_4$ in the regime of strong electronic correlations within an LDA+GTB method, which combines the local density approximation (LDA) and the generalized tight-binding method (GTB). The two mechanisms of band structure doping dependence were taken into account. Namely, the one-electron mechanism provided by the doping dependence of the crystal structure, and the many-body mechanism provided by the strong renormalization of the fermionic quasiparticles due to the large on-site Coulomb repulsion. We have shown that in the antiferromagnetic and in the strongly correlated paramagnetic phases of the underdoped cuprates the main contribution to the doping evolution of band structure and Fermi surface comes from the many-body mechanism.

15 pages, 4 figures, new references and their discussion added, figures updated

References in corpus (3)

• A new hybrid LDA and Generalized Tight-Binding method for the electronic structure calculations of strongly correlated electron systems
• Doping-dependent evolution of low-energy excitations and quantum phase transitions within effective model for High-Tc copper oxides
• Prediction of the in-Gap States Above the Top of the Valence Band in the Undoped Insulating Cuprates due to Spin-Polaron Effect