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arXiv · 1209.3874

Response functions in multicomponent Luttinger liquids

E. Orignac·R. Citro
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Abstract

We derive an analytic expression for the zero temperature Fourier transform of the density-density correlation function of a multicomponent Luttinger liquid with different velocities. By employing Schwinger identity and a generalized Feynman identity exact integral expressions are derived, and approximate analytical forms are given for frequencies close to each component singularity. We find power-like singularities and compute the corresponding exponents. Numerical results are shown for the case of three components.

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E. Orignac, R. Citro. 2012-09-18. Response functions in multicomponent Luttinger liquids. https://doi.org/10.1088/1742-5468%2F2012%2F12%2Fp12020

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