Pseudogap Induced by the SC Fluctuation:: Higher Order Correction Beyond the T-Matrix Approximation.

We discuss the pseudogap phenomena in High-T[sub c] superconductors. The superconducting fluctuation is taken into account as an origin of the pseudogap. Then, the T-matrix approach has been widely used. We report a development along this line. The higher order correction, which is important to capture the effects of the SC fluctuation more precisely, is investigated. It is shown that the vertex correction, which is not included in the self-consistent T-matrix approximation, enhances the pseudogap. [ABSTRACT FROM AUTHOR]