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arXiv · 0801.2921

Crossover from Thermal Activation to Quantum Interlayer Transport at the Superconducting Transition Temperature of Bi-2212

S. O. Katterwe·A. Rydh·V. M. Krasnov
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Abstract

We perform a detailed study of temperature, bias and doping dependance of interlayer transport in the layered high temperature superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$. We observe that the shape of interlayer characteristics in underdoped crystals exhibit a remarkable crossover at the superconducting transition temperature: from thermal activation-type at $T>T_c$, to almost $T-$independent quantum tunneling-type, at $T<T_c$. Our data indicates that the interlayer transport mechanism may change with doping: from the conventional single quasiparticle tunneling in overdoped, to a progressively increasing Cooper pair contribution in underdoped crystals.

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S. O. Katterwe, A. Rydh, V. M. Krasnov. 2008-01-18. Crossover from Thermal Activation to Quantum Interlayer Transport at the Superconducting Transition Temperature of Bi-2212. https://arxiv.org/abs/0801.2921

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