  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.
