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Instabilities in Luttinger liquids

D. C. Cabra·J. E. Drut
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Abstract

We discuss the appearance of magnetic and charge instabilities, named respectively metamagnetism (MM) and phase separation (PS), in systems which can be described by a perturbed Luttinger liquid. We argue that such instabilities can be associated with the vanishing of the effective Fermi velocity v, which in some cases coincides with a divergence of the effective Luttinger parameter K. We analyze in particular an XXZ chain with next-nearest-neighbor interactions in different limits where MM shows up and an extended Hubbard model where in turn, PS occurs. Qualitative agreement with previous studies is found.

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D. C. Cabra, J. E. Drut. 2002-05-06. Instabilities in Luttinger liquids. https://doi.org/10.1088/0953-8984%2F15%2F9%2F308

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