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تسجيل مستخدم جديدAppearance of Universal Metallic Dispersion in a Doped Mott Insulator
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We have investigated the dispersion renormalization $Z_{disp}$ in La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) over the wide doping range of $x=0.03-0.30$, for binding energies extending to several hundred meVs. Strong correlation effects conspire in such a way that the system exhibits an LDA-like dispersion which essentially `undresses ($Z_{disp}to 1$) as the Mott insulator is approached. Our finding that the Mott insulator contains `nascent or `preformed metallic states with a vanishing spectral weight offers a challenge to existing theoretical scenarios for cuprates.
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Detailed understanding of the role of single dopant atoms in host materials has been crucial for the continuing miniaturization in the semiconductor industry as local charging and trapping of electrons can completely change the behaviour of a device.
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