Exotic superconductivity that appears near the charge ordering instability has attracted
significant interest since the beginning of superconducting study. The discovery of possible …

accepted February 20, 2006; published May 10, 2006) Theoretical studies on charge
ordering phenomena in quarter-filled molecular (organic) conductors are reviewed …

Recent developments in research into superconductivity in organic materials are reviewed.
In the epoch-defining quasi-one-dimensional TMTSF superconductors with T c∼ 1 K, T c …

We theoretically examine superconductivity in quasi-two-dimensional organic conductor, α-
(ET) 2 I 3 salt, which has been found under uniaxial pressure and at temperature below the …

The effect of geometrical frustration in a two-dimensional 1∕ 4-filled strongly correlated
electron system is studied theoretically, motivated by layered organic molecular crystals. An …

We preform a multi-orbital analysis on the novel superconductivity in Na x CoO 2· y H 2 O.
We construct a three-orbital model which reproduces the band structure expected from the …

We investigate low-temperature electronic properties of the nondimeric organic
superconductor β′′-(ET) 4 [(H 3 O) Ga (C 2 O 4) 3] Ph NO 2. By examining ultrasonic …

Motivated by the various physical properties observed in θ-(BEDT-TTF) 2 X, we study the
ground state of an extended Hubbard model on two-dimensional anisotropic triangular …

The relationship between the conducting behavior and the degree of charge fluctuation in
the β ″-type BEDT-TTF salts is reviewed from the standpoints of vibrational spectroscopy …

Layered organic superconductors are on the verge of the Mott insulator. We use the
Gutzwiller variational method to study a two-dimensional Hubbard model including a spin …