6533b7d8fe1ef96bd126abad

RESEARCH PRODUCT

Preparation, scaling behavior of activation energy, Hall effect, and flux-flow anisotropy of (Hg0.9Re0.1)Ba2CaCu2O6+δHTS thin films

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Abstract We have prepared fully textured (Hg0.9Re0.1)Ba2CaCu2O6+δ (HgRe-1212) thin films by pulsed laser deposition (PLD) and post-annealing. The films exhibit sharp superconducting transitions at Tc=124 K with transition width ΔTc≃2 K. Conditions for reproducible film preparation have been found. The resistive transitions have been investigated in magnetic fields up to 8 T (parallel to the c-axis) and 10 T (perpendicular to the c-axis). We have determined the activation energy of thermally activated flux-motion for both magnetic field orientations. The Hall resistivity (ρxy) of HgRe-1212 superconductor thin films has been measured in the ab-plane at 8 T. In the mixed state a power-law behavior is observed, where ρxy scales to a power-law function of ρxx: ρxy=Aρβxx, with β=1.4±0.1. Above 130 K the T2 dependence of the cotangent of the Hall angle is observed. At different temperatures magnetization loops were measured with a magnetic field applied normal to the film in a SQUID magnetometer and the corresponding critical current densities Jc were calculated. Under variation of the angle θ between the field direction and the c-axis of the film the anisotropic properties of the vortex state and the depinning field Bdp(θ) have been studied. The measured angular dependence Bdp(θ) shows a cusp for θ=90°. The films exhibit a rather low critical field anisotropy of 7.7.