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Evidence for coexistence of the superconducting gap and the pseudo - gap in Bi-2212 from intrinsic tunneling spectroscopy

V. M. Krasnov·A. Yurgens·D. Winkler·P. Delsing·T. Claeson
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Abstract

We present intrinsic tunneling spectroscopy measurements on small Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ mesas. The tunnel conductance curves show both sharp peaks at the superconducting gap voltage and broad humps representing the $c$-axis pseudo-gap. The superconducting gap vanishes at $T_c$, while the pseudo-gap exists both above and below $T_c$. Our observation implies that the superconducting and pseudo-gaps represent different coexisting phenomena.

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V. M. Krasnov, A. Yurgens, D. Winkler, P. Delsing, T. Claeson. 2000-02-11. Evidence for coexistence of the superconducting gap and the pseudo - gap in Bi-2212 from intrinsic tunneling spectroscopy. https://doi.org/10.1103/physrevlett.84.5860

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