Topological invariants for the Haldane phase of interacting SSH chains -- a functional RG approach

Björn Sbierski; Christoph Karrasch

doi:10.1103/physrevb.98.165101

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arXiv · 1805.00839

Topological invariants for the Haldane phase of interacting SSH chains -- a functional RG approach

Björn Sbierski·Christoph Karrasch

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Abstract

We present a functional renormalization group approach to interacting topological Green function invariants with a focus on the nature of transitions. The method is applied to chiral symmetric fermion chains in the Mott limit that can be driven into a Haldane phase. We explicitly show that the transition to this phase is accompanied by a zero of the fermion Green function. Our results for the phase boundary are quantitatively benchmarked against DMRG data.

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Björn Sbierski, Christoph Karrasch. 2018-05-02. Topological invariants for the Haldane phase of interacting SSH chains -- a functional RG approach. https://doi.org/10.1103/physrevb.98.165101

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