Giant vortex state in perforated aluminum microsquares
Abstract
We investigate the nucleation of superconductivity in a uniform perpendicular magnetic field H in aluminum microsquares containing a few (2 and 4) submicron holes (antidots). The normal/superconducting phase boundary T_c(H) of these structures shows a quite different behavior in low and high fields. In the low magnetic field regime fluxoid quantization around each antidot leads to oscillations in T_c(H), expected from the specific sample geometry, and reminiscent of the network behavior. In high magnetic fields, the T_c(H) boundaries of the perforated and a reference non-perforated microsquare reveal cusps at the same values of Phi/Phi_0 (where Phi is the applied flux threading the total square area and Phi_0 is the superconducting flux quantum), while the background on T_c(H) becomes quasi-linear, indicating that a giant vortex state is established. The influence of the actual geometries on T_c(H) is analyzed in the framework of the linearized Ginzburg-Landau theory.
Cite
@article{arxiv.cond-mat/9905093,
title = {Giant vortex state in perforated aluminum microsquares},
author = {V. Bruyndoncx and J. G. Rodrigo and T. Puig and L. Van Look and V. V. Moshchalkov and R. Jonckheere},
journal= {arXiv preprint arXiv:cond-mat/9905093},
year = {2009}
}
Comments
14 pages, 6 PS figures, RevTex, accepted for publication in Phys. Rev. B