Charge distributions in mesoscopic superconducting rings

The charge distribution in thin mesoscopic superconducting ring is studied by the phenomenological Ginzburg-Landau theory. In the giant vortex states we find that the mesoscopic rings may present three kinds of charge distribution while the disk only owns the first two kinds. The charge near the inner radius may change its sign from negative to positive with increasing applied field. In the multivortex state we find that there exist saddle-point states and stable multivortex states. The distribution of charge and the superconducting electron density in the (0:2) saddle states and the (0:4), and (1:5) stable multivortex states has also been studied. The contour plot of the charge distribution and the Cooper pair density distribution are given.