Chiral d+is superconducting state in the two dimensional t-t' Hubbard model

Applying the recently developed variational approach to Kohn-Luttinger superconductivity to the t-t' Hubbard model in two dimensions, we have found, for sizeable next-nearest neighbor hopping, an electron density controlled quantum phase transition between a d-wave superconducting state close to half filling and an s-wave superconductor at lower electron density. The transition occurs via an intermediate time reversal breaking d+is superconducting phase, which is characterized by nonvanishing chirality and density-current correlation. Our results suggest the possibility of a bulk time reversal symmetry breaking state in overdoped cuprates

An implicit Keller box approach for solution of MHD three-dimensional flow through a porous medium

The present study investigates the Soret and Dufour effect on free-convection flow of a viscous incompressible fluid through a porous medium bounded by an infinite vertical porous plate with chemical reaction and viscous dissipation is investigated with aid of Implicit Keller box and regular perturbation methods. The flow is assumed in the presence of transverse magnetic field. Characteristics of Velocity, Temperature and Concentration are obtained and graphical interpretation is made. The observation of these results reflects that velocity and thermal boundary layer thickness decrease with the increase of radiation parameter. Graphical interpretations establish a good agreement in a realistic sense