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Two-Dimensional Fluctuations Close to the Zero-Field Transition of Bi_2Sr_2CaCu_2O_8

J. Kötzler·M. Kaufmann
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Abstract

The ac-conductivity along the CuO$_2$-layers of epitaxial films and single crystals of thicknesses 0.2$μ$m$\leq L_z \leq130μ$m reveals clear signatures for 2D-ordering. In particular, at $T_c$ the screening length assumes the universal value $L_zΛ_{T_c}/2ν_s$ predicted by the Kosterlitz-Thouless theory, which indicates that binding of long vortex strings nucleates long-range superconductivity in the present samples containing up to $10^5$ CuO$_2$-layers. Several details of the order-parameter dynamics remain unexplained.

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J. Kötzler, M. Kaufmann. 1997-09-05. Two-Dimensional Fluctuations Close to the Zero-Field Transition of Bi_2Sr_2CaCu_2O_8. https://doi.org/10.1103/physrevb.56.13734

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