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Vortex dynamics and states of artificially layered superconducting films with correlated defects

Andreas Engel·H. J. Trodahl
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Abstract

Linear resistances and $IV$-characteristics have been measured over a wide range in the parameter space of the mixed phase of multilayered a-TaGe/Ge films. Three films with varying interlayer coupling and correlated defects oriented at an angle $\approx 25$ from the film normal were investigated. Experimental data were analyzed within vortex glass models and a second order phase transition from a resistive vortex liquid to a pinned glass phase. Various vortex phases including changes from three to two dimensional behavior depending on anisotropy have been identified. Careful analysis of $IV$-characteristics in the glass phases revealed a distinctive $T$ and $H$-dependence of the glass exponent $μ$. The vortex dynamics in the Bose-glass phase does not follow the predicted behavior for excitations of vortex kinks or loops.

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Andreas Engel, H. J. Trodahl. 2002-04-16. Vortex dynamics and states of artificially layered superconducting films with correlated defects. https://doi.org/10.1103/physrevb.66.184505

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