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تسجيل مستخدم جديدSuperconducting coherence peak in the electronic excitations of a single layer cuprate superconductor $Bi_2 Sr_{1.6} La_{0.4} Cu O_{6+delta}$
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Angle resolved photoemission spectroscopy study is reported on a high quality optimally doped Bi2Sr1.6La0.4CuO6+delta high Tc superconductor. In the antinodal region with maximal d-wave gap, the symbolic superconducting coherence peak, which has been widely observed in multi-CuO2-layer cuprate superconductors, is unambiguously observed in a single layer system. The associated peak-dip separation is just about 19 meV, which is much smaller than its counterparts in multi-layered compounds, but correlates with the energy scales of spin excitations in single layer cuprates.
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By in-situ change of polarization a small splitting of the Zhang-Rice singlet state band near the Fermi level has been resolved for optimum doped (x=0.4) Bi$_{2}$Sr$_{2-x}$La$_{x}$CuO$_{6+delta}$ at the (pi,0)-point (R.Manzke et al. PRB 63, R100504 (
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