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Spectral functions and optical conductivity of spinless fermions on a checkerboard lattice

F. Pollmann·P. Fulde·E. Runge
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Abstract

We study the dynamical properties of spinless fermions on the checkerboard lattice. Our main interest is the limit of large nearest-neighbor repulsion $V$ as compared with hopping $|t|$. The spectral functions show broad low-energy excitation which are due to the dynamics of fractionally charged excitations. Furthermore, it is shown that the fractional charges contribute to the electrical current density.

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F. Pollmann, P. Fulde, E. Runge. 2006-04-05. Spectral functions and optical conductivity of spinless fermions on a checkerboard lattice. https://doi.org/10.1103/physrevb.73.125121

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