Resonating-Valence-Bond Approaches to High-Temperature Superconductivity

摘要: This thesis is devoted to a theoretical study of high-temperature superconductivity from the viewpoint doped Mott insulator. To this end, square-lattice t-J model analyzed by variational and mean-field approaches. The focuses on construction excitations spectral properties in framework Anderson's concept resonating-valence-bond wavefunctions. quantum dimer as toy for phase insulators also explored. In first part thesis, single-particle Green's functions superconducting are using Gutzwiller-projected wavefunctions model. It found that overall weight reduced momentum-dependent renormalization, projection produces particle-hole asymmetry renormalization weights. second analyzes pseudogap cuprates within an SU(2) approach where order parameter fluctuates between d-wave superconductor non-superconducting staggered-flux state. predicts photoemission spectrum with asymmetric gap structure interpolating centered at Fermi energy gap. changes sign "hot-spots" surface crosses diagonal (0,π)-(π,0). last single hole vortex liquid triangular-lattice Rokhsar-Kivelson considered. motion bound topological excitation strongly constrained due interference effects.