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arXiv · 1307.0760

Luttinger parameters of interacting fermions in 1D at high energies

O. Tsyplyatyev·A. J. Schofield
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Abstract

Interactions between electrons in one-dimension are fully described at low energies by only a few parameters of the Tomonaga-Luttinger model which is based on linearisation of the spectrum. We consider a model of spinless fermions with a short range interaction via the Bethe-Ansatz technique and show that a Luttinger parameter emerges in an observable beyond the low energy limit. A distinct feature of the spectral function, the edge that marks the lowest possible excitation energy for a given momentum, is parabolic for arbitrary momenta and the prefactor is a function of the Luttinger parameter, K.

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O. Tsyplyatyev, A. J. Schofield. 2013-07-02. Luttinger parameters of interacting fermions in 1D at high energies. https://doi.org/10.1103/physrevb.88.115142

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