Although a triangular vortex lattice is stable in a bulk type-II superconductor, exotic vortex configurations are expected to appear in a small superconducting plate. Theoretical calculations on vortex structures in a star-shaped superconducting plate have been given in our preceding work. In this work, we extended our theoretical studies to the case of having an artificial pin. We performed the Ginzburg-Landau (GL) calculations systematically to compare with the pin-free case by using the finite element method. We found that a vortex tends to accommodate preferentially in an aritificial pin in the star-shaped plate. We found a systematic evolution of vortex structure with increaseing magnetic field. We compare our theoretical calculations with vortices in a star-shaped Mo80Ge20 plate with an artificial pin and without an artificial pin obtained by a scanning SQUID microscope. We reconstructed the vortex image on the sample surface by using the inverse Biot-Savart law and the Fourier transformation.
[1]
H. T. Huy,et al.
Vortex distribution in amorphous Mo80Ge20 plates with artificial pinning center
,
2016
.
[2]
S. Okayasu,et al.
Direct Imaging of Vortex Polygons and Vortex Shells in Mesoscopic Squares of a Weak Pinning Superconducting Thin Film
,
2014
.
[3]
H. T. Huy,et al.
Vortex structures in nano-sized pentagon and other shaped superconductors
,
2013
.
[4]
J. Aguiar,et al.
Vortex configurations in thin superconducting equilateral triangles
,
2009
.
[5]
F. Peeters,et al.
Formation and Size-Dependence of Vortex Shells in Mesoscopic Superconducting Niobium Disks
,
2007,
0804.1817.