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Flux-flow resistivity anisotropy in the instability regime in the a-b plane of epitaxial YBCO thin films

B. Kalisky·P. Aronov·G. Koren·A. Shaulov·Y. Yeshurun·R. P. Huebener
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Abstract

Measurements of the nonlinear flux-flow resistivity $ρ$ and the critical vortex velocity $\rm v^*_ϕ$ at high voltage bias close to the instability regime predicted by Larkin and Ovchinnikov \cite{LO} are reported along the node and antinode directions of the d-wave order parameter in the \textit{a-b} plane of epitaxial $YBa_2Cu_3O_{7-δ}$ films. In this pinning-free regime, $ρ$ and $\rm v^*_ϕ$ are found to be anisotropic with values in the node direction larger on average by 10% than in the antinode direction. The anisotropy of $ρ$ is almost independent of temperature and field. We attribute the observed results to the anisotropic quasiparticle distribution on the Fermi surface of $YBa_2Cu_3O_{7-δ}$.

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B. Kalisky, P. Aronov, G. Koren, A. Shaulov, Y. Yeshurun, R. P. Huebener. 2006-06-26. Flux-flow resistivity anisotropy in the instability regime in the a-b plane of epitaxial YBCO thin films. https://doi.org/10.1103/physrevlett.97.067003

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