The structures, the phase diagrams, and the appearance of a neutron resonance signaling
an unconventional superconducting state provide phenomenological evidence relating the …

In narrow-band systems electrons can interact with each other via a short-range nonretarded
attractive potential. The origin of such an effective local attraction can be polaronic or it can …

Presenting the physics of the most challenging problems in condensed matter using the
conceptual framework of quantum field theory, this book is of great interest to physicists in …

The elementary CuO2 plane sustaining cuprate high-temperature superconductivity occurs
typically at the base of a periodic array of edge-sharing CuO5 pyramids. Virtual transitions of …

A large-N expansion technique based on symplectic [Sp (N)] symmetry for frustrated
magnetic systems is proposed and applied to the square-lattice quantum antiferromagnet …

The spin-½ antiferromagnetic Heisenberg model on a square lattice is used to describe the
dynamics of the spin degrees of freedom of undoped copper oxides. Even though the model …

A model of copper-oxygen bonding and antibonding bands with the most general two-body
interactions allowable by symmetry is considered. The model has a continuous transition as …

We describe a unitary transformation which eliminates terms coupling states with differing
numbers of doubly occupied sites from the Hamiltonian of the Hubbard model. The S matrix …

We describe the confining instabilities of a proposed quantum spin liquid underlying the
pseudogap metal state of the hole-doped cuprates. The spin liquid can be described by a …

Superconducting gap anisotropy at least an order of magnitude larger than that of the
conventional superconductors has been observed in the ab plane of Bi 2 Sr 2 CaCu 2 O 8+ …