Model study of antiferromagnetism in high-tc superconducting oxides

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Absence of pairing mechanism due to coupling of oxygen holes to localized spins in high-tc superconductors

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Quasiparticles in the spin-fermion model for CuO2 planes

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Spin polarons in the t-t'-j model

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Quantum melting of magnetic order due to orbital fluctuations

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Effective d(8) model - phase-diagram

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Origin of band and localized electron states in photoemission of NiO

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Zhang-rice localization and quasi-particles in cuo2 planes

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

How strongly are electrons correlated in the high-tc superconducting materials

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Stripe phases — possible ground state of the high-Tc superconductors

Based on the mean-field method applied either to the extended single-band Hubbard model or to the single-band Peierls-Hubbard Hamiltonian we study the stability of both site-centered and bond-centered charge domain walls. The difference in energy between these phases is found to be small. Therefore, moderate perturbations to the pure Hubbard model, such as next nearest neighbor hopping, lattice anisotropy, or coupling to the lattice, induce phase transitions, shown in the corresponding phase diagrams. In addition, we determine for stable phases charge and magnetization densities, double occupancy, kinetic and magnetic energies, and investigate the role of a finite electron-lattice coupling. We also review experimental signatures of stripes in the superconducting copper oxides