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On the Origin of the Tunneling Asymmetry in the Cuprate Superconductors

Tao Li·Fan Yang·Yong-Jin Jiang
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Abstract

We argue the coherent part of the spectral weight always contribute symmetrically to the STM spectrum at sufficiently low energy and the tunneling asymmetry is a manifestation of the incoherent part of the electron spectrum. By subtracting the particle side spectrum from the hole side spectrum in the published STM data of Pan \textit{et al} on $BSCCO_{2212}(T_{c}=84K)$, we find the difference spectrum show a well defined gap structure at 25 meV. We argue this gap may represent a new energy scale of the system, namely the energy scale for spin-charge recombination in this system.

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Tao Li, Fan Yang, Yong-Jin Jiang. 2004-06-04. On the Origin of the Tunneling Asymmetry in the Cuprate Superconductors. https://arxiv.org/abs/cond-mat/0406095

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