6 papers · 1 filter
Spin polarized current and Andreev transmission in planar superconducting/ferromagnetic Nb/Ni junctions
E. M. González, A. D. Folgueras, R. Escudero +3
We have measured the tunnelling current in Nb/NbO/Ni planar tunnel junctions at different temperatures. The junctions are in the intermediate transparency regime. We have e…
Lattice effects and current reversal in superconducting ratchets
L. Dinis, E. M. Gonzalez, J. V. Anguita +2
Competition between the vortex lattice and a lattice of asymmetric artificial defects is shown to play a crucial role in ratchet experiments in superconducting films. We present a…
Vortex-glass transition in superconducting Nb/Cu superlattices
J. E. Villegas, J. L. Vicent
Nb/Cu superconducting superlattices have been fabricated by dc magnetron sputtering. This system shows a vortex glass transition with critical exponents similar to high temperature…
Experimental ratchet effect in superconducting films with periodic arrays of asymmetric potentials
J. E. Villegas, E. M. Gonzalez, M. P. Gonzalez +2
A vortex lattice ratchet effect has been investigated in Nb films grown on arrays of nanometric Ni triangles, which induce periodic asymmetric pinning potentials. The vortex lattic…
Spin polarized current and Andreev transmission in planar superconducting-ferromagnetic Nb-Ni junctions
E. M. Gonzalez, A. Dominguez-Folgueras, F. J. Palomares +6
We have measured and modeled, using three different approaches, the tunneling current in a Nb/NbxOy/Ni planar tunnel junction. The experimental data could be fitted and the correct…
Directional vortex motion guided by artificially induced mesoscopic potentials
J. E. Villegas, E. M. Gonzalez, M. I. Montero +2
Rectangular pinning arrays of Ni dots define a potential landscape for vortex motion in Nb films. Magnetotransport experiments in which two in-plane orthogonal electrical currents…