Quantum mott transition and superconductivity

The gas-liquid transition is a first-order transition terminating at a finite-temperature critical point with diverging density fluctuations. The Mott transition, a metal-insulator transition driven by Coulomb repulsion between electrons, has been identified with this textbook transition. However, the critical temperature of the Mott transition can be suppressed, leading to unusual quantum criticality, which results in a breakdown of the conventional Ginzburg-Landau-Wilson scheme. This accounts for non-Fermi-liquid-like properties, and strongly momentum-dependent quasiparticles as in many materials near the Mott insulator. Above all, the mode-coupling theory of the density fluctuations supports d-wave superconductivity at the order of 100 K for the relevant parameters of copper oxide superconductors.