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arXiv · 1510.01519

Luttinger liquid with complex forward scattering: robustness and Berry phase

Balázs Dóra·Roderich Moessner
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Abstract

Luttinger liquids (LLs) are one dimensional systems with well-understood instabilities due to umklapp or backscattering. We study a generalization of the Luttinger model, which incorporates a time reversal symmetry breaking interaction producing a complex forward scattering amplitude ($g_2$ process). The resulting low energy state is still a LL, and belongs to the family of interacting Schulz-Shastry models. Remarkably, it becomes increasingly robust against additional perturbations -- for purely imaginary $g_2$, both umklapp and local backscattering are always irrelevant. Changing the phase of the interaction generates a non-trivial Berry phase, with a universal geometric phase difference between ground and a one boson excited state depending only on the LL parameter.

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Balázs Dóra, Roderich Moessner. 2015-10-06. Luttinger liquid with complex forward scattering: robustness and Berry phase. https://doi.org/10.1103/physrevb.93.075127

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