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Pseudo-gap features of intrinsic tunneling in (HgBr_2)-Bi2212 single crystals

A. Yurgens·D. Winkler·T. Claeson·Seong-Ju Hwang·Jin-Ho Choy
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Abstract

The c-axis tunneling properties of both pristine Bi2212 and its HgBr$_2$ intercalate have been measured in the temperature range 4.2 - 250 K. Lithographically patterned 7-10 unit-cell heigh mesa structures on the surfaces of these single crystals were investigated. Clear SIS-like tunneling curves for current applied in the $\it c$-axis direction have been observed. The dynamic conductance d$I/$d$V(V)$ shows both sharp peaks corresponding to a superconducting gap edge and a dip feature beyond the gap, followed by a wide maximum, which persists up to a room temperature. Shape of the temperature dependence of the {\it c}-axis resistance does not change after the intercalation suggesting that a coupling between $\rm CuO_2$-bilayers has little effect on the pseudogap.

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A. Yurgens, D. Winkler, T. Claeson, Seong-Ju Hwang, Jin-Ho Choy. 1999-07-10. Pseudo-gap features of intrinsic tunneling in (HgBr_2)-Bi2212 single crystals. https://doi.org/10.1142/s0217979299003878

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