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arXiv · 1102.2990

Magnetic torque study of the temperature dependent anisotropy parameter in overdoped superconducting single-crystal YBa_2Cu_3O_7

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

An overdoped YBa2Cu3O7 single crystal was studied by SQUID and torque magnetometry in order to investigate the temperature dependence of the anisotropy parameter close to the transition temperature T_c (0.87 T_c < T < T_c). Angle dependent torque measurements were performed and analyzed with the widely used Kogan model [Phys. Rev. B 38, 7049 (1988)] as well as with an extended model by Hao and Clem [Phys. Rev. Lett. 67, 2371 (1991)], taking into account the influence of the vortex cores on the magnetization. Both approaches yield similar results, with an out-of-plane anisotropy parameter around 6.5 which slightly increases with decreasing temperature, and a temperature independent in-plane anisotropy parameter gamma_ab}= 1.12(5).

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S. Bosma, S. Weyeneth, R. Puzniak, A. Erb, A. Schilling, H. Keller. 2011-07-13. Magnetic torque study of the temperature dependent anisotropy parameter in overdoped superconducting single-crystal YBa_2Cu_3O_7. https://doi.org/10.1103/physrevb.84.024514

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