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The Origin of the Pseudogap from Tunneling Spectroscopy Measurements on Bi-2212 Single Crystals

A. Mourachkine
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Abstract

We present electron-tunneling spectroscopy of oxygen over- and under-doped Bi-2212 single crystals in a temperature range between 14 K and 290 K using a break-junction technique. In over- and under-doped samples we observe a pseudogap with T* = 280 - 290 K and T* > 290 K, respectively. In order to explain the data we consider possible models for the pseudogap, namely, (i) a precursor pairing; (ii) a charge-density-wave gap; (iii) a spin-gap due to antiferromagnetic (AF) correlations. Analyzing all data we show unambiguously that the only model which fits the data is a gap due to AF correlations.

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A. Mourachkine. 1998-10-15. The Origin of the Pseudogap from Tunneling Spectroscopy Measurements on Bi-2212 Single Crystals. https://arxiv.org/abs/cond-mat/9810161

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