A pr 1 99 4 Temperature dependence of the superconducting gap anisotropy in Bi
نویسندگان
چکیده
We present the first detailed data of the momentum-resolved, temperature dependence of the superconducting gap of Bi 2 Sr 2 Ca 1 Cu 2 O 8+x , complemented by similar data on the intensity of the photoemission superconducting conden-sate spectral area. The gap anisotropy between the Γ− ¯ M and Γ−X directions increases markedly with increasing temperature, contrary to what happens for conventional anisotropic-gap superconductors such as lead. Specifically, the size of the superconducting gap along the Γ − X direction decreases to values indistinguishable from zero at temperatures for which the gap retains virtually full value along the Γ − ¯ M direction.
منابع مشابه
Temperature dependent gap anisotropy from interlayer tunneling
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