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Fractionnally charged excitations in the charge density wave state of a quarter-filled t-J chain with quantum phonons

Philippe Maurel·Marie-Bernadette Lepetit·Didier Poilblanc
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Abstract

Elementary excitations of the 4k$_F$ charge density wave state of a quarter-filled strongly correlated electronic one-dimensional chain are investigated in the presence of dispersionless quantum optical phonons using Density Matrix Renormalization Group techniques. Such excitations are shown to be topological unbound solitons carrying charge $e/2$. Relevance to the 4k$_F$ charge density wave instability in $\rm (DI-DCNQI)_2Ag$ or recently discovered in (TMTTF)$_2$X (X=PF$_6$, AsF$_6$) is discussed.

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Philippe Maurel, Marie-Bernadette Lepetit, Didier Poilblanc. 2001-01-25. Fractionnally charged excitations in the charge density wave state of a quarter-filled t-J chain with quantum phonons. https://doi.org/10.1007/s100510170156

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