Nucleation of superconductivity in mesoscopic star-shaped superconductors

Suppression of superconductivity in mesoscopic superconductors.

We propose a new boundary-driven phase transition associated with vortex nucleation in mesoscopic superconductors (of size of the order of, or larger than, the penetration depth). We derive the rescaling equations and we show that boundary effects associated with vortex nucleation lower the conventional transition temperature in mesoscopic superconductors by an amount which is a function of the...

Mesoscopic Effects in Superconductivity

Local destruction of superconductivity by non-magnetic impurities in mesoscopic iron-based superconductors

The determination of the pairing symmetry is one of the most crucial issues for the iron-based superconductors, for which various scenarios are discussed controversially. Non-magnetic impurity substitution is one of the most promising approaches to address the issue, because the pair-breaking mechanism from the non-magnetic impurities should be different for various models. Previous substitutio...

Nucleation of superconductivity in finite anisotropic superconductors and the evolution of surface superconductivity toward the bulk mixed state

In anisotropic superconductors having an arbitrary orientation of the sample surface relative to the crystal principal axes, the surface critical field Hc3 is less than 1.695Hc2 unless the field is situated along one of the principal crystal planes. Below Hc3 in the vicinity of nucleation, the order parameter scales as AHc32H . Computational studies for infinite cylinders having rectangular cro...

Flux Confinement in Mesoscopic Superconductors

We report on flux confinement effects in superconducting submicron line, loop and dot structures. The main idea of our study was to vary the boundary conditions for confinement of the superconducting condensate by taking samples of different topology and, through that, modifying the lowest Landau level ELLL(H). Since the critical temperature versus applied magnetic field Tc(H) is, in fact, ELLL...