Edge states in non-Fermi liquids

Igor V. Yurkevich

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arXiv · 1702.06406

Edge states in non-Fermi liquids

Igor V. Yurkevich

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Abstract

We devise an approach to the calculation of scaling dimensions of generic operators describing scattering within multi-channel Luttinger liquid. The local impurity scattering in an arbitrary configuration of conducting and insulating channels is investigated and the problem is reduced to a single algebraic matrix equation. In particular, the solution to this equation is found for a finite array of chains described by Luttinger liquid models. It is found that for a weak inter-chain hybridisation and intra-channel electron-electron attraction the edge wires are robust against disorder whereas bulk wires, on contrary, become insulating. Thus, the edge state may exist in a finite sliding Luttinger liquid without time-reversal symmetry breaking (quantum Hall systems) or spin-orbit interaction (topological insulators).

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Igor V. Yurkevich. 2017-02-21. Edge states in non-Fermi liquids. https://arxiv.org/abs/1702.06406

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