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Impurity-Induced Bound Excitations on the Surface of Bi2Sr2CaCu2O8

Ali Yazdani·C. M. Howald·C. P. Lutz·A. Kapitulnik·D. M. Eigler
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Abstract

We have probed the effects of atomic-scale impurities on superconductivity in Bi_{2}Sr_{2}CaCu_{2}O_{8} by performing low-temperature tunneling spectroscopy measurements with a scanning tunneling microscope. Our results show that non-magnetic defect structures at the surface create localized low-energy excitations in their immediate vicinity. The impurity-induced excitations occur over a range of energies including the middle of the superconducting gap, at the Fermi level. Such a zero bias state is a predicted feature for strong non-magnetic scattering in a d-wave superconductor.

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Ali Yazdani, C. M. Howald, C. P. Lutz, A. Kapitulnik, D. M. Eigler. 1999-06-01. Impurity-Induced Bound Excitations on the Surface of Bi2Sr2CaCu2O8. https://doi.org/10.1103/physrevlett.83.176

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