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Spectroscopic signatures of spin-charge separation in the quasi-one-dimensional organic conductor TTF-TCNQ

R. Claessen·M. Sing·U. Schwingenschloegl·P. Blaha·M. Dressel·C. S. Jacobsen
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Abstract

The electronic structure of the quasi-one-dimensional organic conductor TTF-TCNQ is studied by angle-resolved photoelectron spectroscopy (ARPES). The experimental spectra reveal significant discrepancies to band theory. We demonstrate that the measured dispersions can be consistently mapped onto the one-dimensional Hubbard model at finite doping. This interpretation is further supported by a remarkable transfer of spectral weight as function of temperature. The ARPES data thus show spectroscopic signatures of spin-charge separation on an energy scale of the conduction band width.

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R. Claessen, M. Sing, U. Schwingenschloegl, P. Blaha, M. Dressel, C. S. Jacobsen. 2002-01-30. Spectroscopic signatures of spin-charge separation in the quasi-one-dimensional organic conductor TTF-TCNQ. https://doi.org/10.1103/physrevlett.88.096402

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