Рубрики:
T-J-MODEL
HIGH-TEMPERATURE SUPERCONDUCTORS
DIMENSIONAL HUBBARD-MODEL
QUASI-PARTICLE DISPERSION
HEISENBERG-ANTIFERROMAGNET SR2CUO2CL2
ANGLE-RESOLVED PHOTOEMISSION
CHARGE FLUCTUATION REGIME
SADDLE-POINT SINGULARITY
SINGLET-TRIPLET MODEL
LA-SR-CU
T-J-MODEL
HIGH-TEMPERATURE SUPERCONDUCTORS
DIMENSIONAL HUBBARD-MODEL
QUASI-PARTICLE DISPERSION
HEISENBERG-ANTIFERROMAGNET SR2CUO2CL2
ANGLE-RESOLVED PHOTOEMISSION
CHARGE FLUCTUATION REGIME
SADDLE-POINT SINGULARITY
SINGLET-TRIPLET MODEL
LA-SR-CU
Аннотация: New experimental and theoretical results on the electronic structure and spectral properties of quasiparticles in cuprate oxides are reviewed. It is shown that the electronic structure transforms from antiferromagnetic insulators to optimally doped high-temperature superconductors as the doping level is varied. The experimental methods considered are primarily angular resolved photoelectron spectroscopy (ARPES), neutron scattering, and NMR. Two types of electronic structure calculations for data interpretation purposes are considered, namely, exact numerical methods for finite clusters (exact diagonalisation and the quantum Monte Carlo method) and approximate schemes for the infinite lattice. As a result, a coherent unified picture emerges, in which the magnetic polaron of a weakly doped antiferromagnetic lattice transforms into a system of Fermi particles dressed by short-range antiferromagnetic type spin fluctuations. In the region of weakly doped metal compositions, deviations from Fermi-liquid properties are seen, such as the failure of Luttinger's theorem, shadowy photoemission bands, and the spin pseudogap effect in spectral and thermodynamic measurements. The situation in the neighbourhood of the insulator-metal concentration transition is described as least understood.
WOS
Доп.точки доступа:
Овчинников, Сергей Геннадьевич