Ginzburg-Landau calculations of d-wave superconducting dot in s-wave superconducting matrix

We have developed a numerical method that calculated superconducting states and magnetic field distributions for the composite structures of the High-Tc superconductor and the conventional superconductor in arbitrary geometries. We show spontaneous magnetic flux appears at the corner of the boundary of these two superconductors. Also we propose High-Tc superconducting dot embedded in conventional superconductors, which is named as d-dot and show the spatial distribution of superconducting order parameters and the magnetic field.