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arXiv · 1208.3062

Vortex lock-in transition coinciding with the 3D to 2D crossover in YBa2Cu3O7

S. Bosma·S. Weyeneth·R. Puzniak·A. Erb·H. Keller
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Abstract

A vortex lock-in transition was directly detected by torque magnetometry in an overdoped YBa2Cu3O7 single crystal of low anisotropy (\approx 7). The locked-in state was observed below the 3D to 2D crossover temperature Tcr = 76 K, independently of extrinsic pinning effects thanks to a high quality clean crystal and the use of a vortex shaking technique. The shape of the torque signal as a function of the angle between the applied magnetic field and the crystallographic c-axis is in very good agreement with the model developped by Feinberg and Ettouhami [Int. J. Mod. Phys. B 7, 2085 (1993)] for quasi-2D superconductors, despite the low anisotropy of the material.

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S. Bosma, S. Weyeneth, R. Puzniak, A. Erb, H. Keller. 2012-08-15. Vortex lock-in transition coinciding with the 3D to 2D crossover in YBa2Cu3O7. https://doi.org/10.1103/physrevb.86.174502

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