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arXiv · 0812.2593

Impurity Scattering Effects in STM Studies of High-T_c Superconductors

Noboru Fukushima·Chung-Pin Chou·Ting Kuo Lee
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Abstract

Recent STM measurements have observed many inhomogeneous patterns of the local density of states on the surface of high-T_c cuprates. As a first step to study such disordered strong correlated systems, we use the BdG equation for the t-t'-t"-J model with an impurity. The impurity is taken into account by a local potential or local variation of the hopping/exchange terms. Strong correlation is treated by a Gutzwiller mean-field theory with local Gutzwiller factors and local chemical potentials. It turned out that the potential impurity scattering is greatly suppressed, while the local variation of hoppings/exchanges is enhanced.

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Noboru Fukushima, Chung-Pin Chou, Ting Kuo Lee. 2008-12-14. Impurity Scattering Effects in STM Studies of High-T_c Superconductors. https://doi.org/10.1016/j.jpcs.2008.06.039

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