Abstract Two different types of monoclinic HfO 2 nanocrystals were employed in this work to study the effect nanocrystal shape and crystallinity on structural defects YBa2Cu3O7−δ (YBCO) matrix as it leads an enhancement pinning performances solution-derived YBCO nanocomposite films. In nanorod-like obtained from surfactant-controlled synthesis led short intergrowths surrounding particles, while...

– 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...

The planar oxygen isotope effect coefficient measured as a function of hole doping in the Prand La-doped YBa2Cu3O7 (YBCO) and the Ni-doped La1.85Sr0.15CuO4 (LSCO) superconductors quantitatively and qualitatively follows the form originally proposed by Kresin andWolf [Phys. Rev. B 49, 3652 (1994)], which was derived for polarons perpendicular to the superconducting planes. Interestingly, the inv...