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Tunneling spectroscopy of Tl2Ba2CaCu2O8 single crystals and thin films

Daniel Mazur·J. F. Zasadzinski·K. E. Gray·Y. C. Ma·N. L. Wang·S. L. Yan
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Abstract

Early electron tunneling experiments with the Tl2Ba2CaCu2O8 measured Δ= 16-28 meV, while bulk optical experiments measured Δ= 43-45 meV. We report new tunneling measurements of Tl2Ba2CaCu2O8 single crystals and c-axis oriented thin films, where the measured Δvalues on both sample types cover the range of 24-50 meV, with more than 70% of the junctions displaying Δ> 30 meV. This work resolves the inconsistency between previously published results of tunneling and optical experiments. New tunneling conductances reveal improved superconducting gap region characteristics consistent with d-wave symmetry. The tunneling spectra also display features similar to the dip feature observed in Bi2Sr2CaCu2O8. We discuss our results in context of experiments reported previously on related materials.

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Daniel Mazur, J. F. Zasadzinski, K. E. Gray, Y. C. Ma, N. L. Wang, S. L. Yan. 2006-11-27. Tunneling spectroscopy of Tl2Ba2CaCu2O8 single crystals and thin films. https://arxiv.org/abs/cond-mat/0611636

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