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Optical conductivity of the half-filled Hubbard chain

E. Jeckelmann·F. Gebhard·F. H. L. Essler
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Abstract

We combine well-controlled analytical and numerical methods to determine the optical conductivity of the one-dimensional Mott-Hubbard insulator at zero temperature. A dynamical density-matrix renormalization group method provides the entire absorption spectrum for all but very small coupling strengths. In this limit we calculate the conductivity analytically using exact field-theoretical methods. Above the Lieb-Wu gap the conductivity exhibits a characteristic square-root increase. For small to moderate interactions, a sharp maximum occurs just above the gap. For larger interactions, another weak feature becomes visible around the middle of the absorption band.

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E. Jeckelmann, F. Gebhard, F. H. L. Essler. 2000-10-27. Optical conductivity of the half-filled Hubbard chain. https://doi.org/10.1103/physrevlett.85.3910

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