Theory of Asymmetric Tunneling in the cuprate superconductors

P. W. Anderson; N. P. Ong

doi:10.1016/j.jpcs.2005.10.132

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Theory of Asymmetric Tunneling in the cuprate superconductors

P. W. Anderson·N. P. Ong

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Abstract

We explain quantitatively, within the Gutzwiller-Resonating Valence Bond theory, the puzzling observation of tunneling conductivity between a metallic point and a cuprate high-$T_c$ superconductor which is markedly asymmetric between positive and negative voltage biases. The asymmetric part does not have a "coherence peak" but does show structure due to the gap. The fit to data is satisfactory within the over-simplifications of the theory; in particular, it explains the marked "peak-dip-hump" structure observed on the hole side and a number of other qualitative observations. This asymmetry is strong evidence for the projective nature of the ground state and hence for "t-J" physics.

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P. W. Anderson, N. P. Ong. 2004-06-01. Theory of Asymmetric Tunneling in the cuprate superconductors. https://doi.org/10.1016/j.jpcs.2005.10.132

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