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Correlation of tunneling spectra with surface nano-morphology and doping in thin YBa2Cu3O7-delta films

A. Sharoni·G. Koren·O. Millo
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Abstract

Tunneling spectra measured on thin epitaxial YBa2Cu3O7-delta films are found to exhibit strong spatial variations, showing U and V-shaped gaps as well as zero bias conductance peaks typical of a d-wave superconductor. A full correspondence is found between the tunneling spectra and the surface morphology down to a level of a unit-cell step. Splitting of the zero bias conductance peak is seen in optimally-doped and overdoped films, but not in the underdoped ones, suggesting that there is no transition to a state of broken time reversal symmetry in the underdoped regime

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A. Sharoni, G. Koren, O. Millo. 2001-03-28. Correlation of tunneling spectra with surface nano-morphology and doping in thin YBa2Cu3O7-delta films. https://doi.org/10.1209/epl%2Fi2001-00368-1

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