Fluctuating bond model of high temperature superconductivity in cuprates

High-temperature interface superconductivity between metallic and insulating cuprates

High-temperature superconductivity confined to nanometer-size interfaces has been a long standing goal because of potential applications 1,2 and the opportunity to study quantum phenomena in reduced dimensions 3,4. However, this is a challenging target: in conventional metals the high electron density restricts interface effects such as carrier depletion/accumulation to a region much narrower t...

Revealing the high-energy electronic excitations underlying the onset of high-temperature superconductivity in cuprates

In strongly correlated systems the electronic properties at the Fermi energy (E(F)) are intertwined with those at high-energy scales. One of the pivotal challenges in the field of high-temperature superconductivity (HTSC) is to understand whether and how the high-energy scale physics associated with Mott-like excitations (|E-E(F)|>1 eV) is involved in the condensate formation. Here, we report t...

Plaquette valence bond theory of high-temperature superconductivity

Superconductivity in the cuprates

We evaluate numerically several superconducting correlation functions in a generalized t − J model derived for hole-doped CuO2 planes. The model includes a three-site term t similar to that obtained in the large U limit of the Hubbard model but of opposite sign for realistic O-O hopping. For realistic parameters we obtain strong evidence of superconductivity of predominantly dx2−y2 character. T...

A Strategy for Higher Temperature Superconductivity in the Layered Cuprates

Recent attempts to raise the critical temperatures of cuprate superconductors are reviewed and discussed in terms of covalent electron transfer between Cu ions of mixed valence. A report of possible superconductivity effects at 250 K is examined from the standpoint of AB02 parent-cell building blocks identified as superconducting by Goodenough and his students at the University of Texas. Based ...