arXiv subjects
Publications and source records attributed to A. Mourachkine.
The disclosure of spinon superconductivity and superconductivity mediated by spin-waves in hole-doped Bi2212 cuprate raises the question about the origin of the superconductivity in other cuprates and specially in an electron-doped NCCO cuprate.
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.
The paper has been withdrawn by the author because the observed effect has a different origin.