Grain Boundary Induced Magneto-Far Infrared Resonances in Superconducting YBa2Cu3O7−δ Thin Films

Critical Current Density of YBa 2 Cu 3 O 7 − δ Low - Angle Grain Boundaries in Self - Field

A study has been perfomed on the superconducting critical current density Jc flowing across low angle grain boundaries in epitaxial thin films of YBa2Cu3O7−δ (YBCO). The materials studied were dual grain boundary rings deposited on SrTiO3 and containing 2 , 3, 5 and 7 tilt boundaries. The current density in self-field was determined by magnetometric methods at temperatures from 5 K to Tc. We co...

Dynamics of the dendritic flux instability in YBa2Cu3O7-δ films

– We have studied the dynamics of magnetic-flux avalanches in superconducting YBa2Cu3O7−δ films by means of a fast magneto-optic pump-probe technique. Two regimes of propagation are found: in regime I, directly after the nucleation of the avalanches by a femtosecond laser pulse, the velocity v of the flux dendrites depends strongly on the magnetic field, and values of v up to 180 km/s are obser...

Nanosecond magneto-optic study of a new instability in thin YBa2Cu3O7-x films

We have investigated the dynamics of flux penetration into thin superconducting YBa2Cu307--x films using a magneto-optic technique with nanosecond time resolution. For films carrying large shielding currents an instability in the magnetic Aux distribution is discovered, which can be triggered by a local’perturbation, e.g., by a focused laser pulse. The instability develops in the form of fine r...

EFFECT OF A COMPRESSIVE UNIAXIAL STRAIN ON THE CRITICAL CURRENT DENSITY OF GRAIN BOUNDARIES IN SUPERCONDUCTING YBa2Cu3O7-δ FILMS (POSTPRINT)

Inhomogeneities in YBa 2Cu 3O 7 thin films with reduced thickness

Morphology and physical properties of mono(YBa2Cu3O7) and multilayered (YBa2Cu3O7/SmBa2Cu3O7/ YBa2Cu3O7) superconducting thin films with thickness ranging from 90 nm to 28 nm have been investigated. For both types of samples, the superconducting properties degraded with reduction of film thickness. Structural and electromagnetic properties were visualized through scanning electron microscopy an...