Related papers: Theory and experiment testing flux-line-cutting ph…
The results of dc, microwave and magnetic measurements of YBCO bicrystal junctions on r-cut sapphire are presented. The junctions with high resistance 10-20 W and IcRN= 1-2 mV and tolerance of RNS around 30% on chip allow to create…
Superconducting thin metallic films, functioning as supercurrent gate-tunable transistors, have considerable potential for future quantum electronic devices. Despite extensive research, a comprehensive microscopic quantitative mechanism…
In this Chapter we review our latest results on magnetic (AC susceptibility) and transport (resistivity) properties of Pr1.85Ce0.15CuO4 (PCCO) and Sm1.85Ce0.15CuO4 (SCCO) thin films grown by pulsed laser deposition technique. Three main…
In type-II superconductors, in the regime of very high applied current density, an abrupt transition is experimentally observed from the mixed state to a highly dissipative regime, probably the normal state. This provokes a high voltage…
We have studied the influence of the patterning procedure on the critical current density of high-$T_c$ YBa$_2$Cu$_3$O$_{7-\delta}$ thin rings using the nonlinear ac susceptibility method. At no applied dc magnetic field we have found that…
Doping is one of the most relevant paths to tune the functionality of cuprates, it determines carrier density and the overall physical properties of these impressive superconducting materials. We present an oxygen doping study of…
We analyze the electrical characteristics of a circuit consisting of a free thin-film magnetic layer and source and drain electrodes that have opposite magnetization orientations along the free magnet's two hard directions. We find that…
A flux line in a Type-II superconductor with a single nonuniform columnar defect is studied by a perturbative diagrammatic expansion around an annealed approximation. The system undergoes a finite temperature depinning transition for the…
The dynamical critical behavior of a single directed line driven in a random medium near the depinning threshold is studied both analytically (by renormalization group) and numerically, in the context of a Flux Line in a Type-II…
We explore the dynamics of driven magnetic flux lines in disordered type-II superconductors in the presence of twin boundaries oriented parallel to the direction of the applied magnetic field, using a three-dimensional elastic line model…
We develop a theoretical framework for planar quasi-ballistic Josephson junctions, where multiple superconducting leads are coupled through a large, nearly ballistic normal metal crystal. Our approach, based on quasiclassical Eilenberger…
The pinning of flux lines by two different types of regular arrays of submicron magnetic dots is studied in superconducting Pb films; rectangular Co dots with in-plane magnetization are used as pinning centers to investigate the influence…
Magnesium diboride superconducting wires give the largest critical current density (Jc) when produced with iron sheath. Because iron is ferromagnetic, it is expected to improve the field dependence of Jc by shielding of the external field…
We study the low temperature dynamics of a single flux line in a bulk type-II superconductor, driven by a surface current, both near and above the onset of an instability which sets in at a critical driving. We found that above the critical…
We propose to use superconductor-magnet multi-layer structure to achieve high critical current density by invoking polaronic mechanism of pinning. The magnetic layers should have large magnetic susceptibility to enhance the coupling between…
Detailed measurements of the critical current density jc of YBa2Cu3O7 films grown by pulsed laser deposition reveal the increase of jc as function of the filmthickness. Both this thickness dependence and the field dependence of the critical…
We have studied nodal tunneling into YBa2Cu3O7-x (YBCO) films under magnetic fields. The films' orientation was such that the CuO2 planes were perpendicular to the surface with the a and b axis at 450 form the normal. The magnetic field was…
Recent experiments have demonstrated the nonequilibrium control of the supercurrent through diffusive phase-coherent normal-metal weak links. The experimental results have been accurately described by the quasiclassical Green's function…
As an example for a seemingly simple but actually intricate problem, the Bean critical state is studied in a superconducting strip of finite thickness d and width 2w >> d placed in an oblique magnetic field. The analytical solution is…
Low-temperature dynamics of flux lines in high temperature, type II, superconductors in the presence of correlated disorder in the form of columnar defects is discussed. The effect of tilting the applied magnetic field with respect to the…