Discrete spectrum of edge states in a two-dimensional topological insulator

A. I. Milstein; I. S. Terekhov

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arXiv · 2503.18390

Discrete spectrum of edge states in a two-dimensional topological insulator

A. I. Milstein·I. S. Terekhov

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Abstract

The interaction model of two electrons in the edge states of a two-dimensional topological insulator is investigated. Both solutions of the Schr\"odinger equation and solutions of the Bethe-Salpeter equation at different values of the Fermi energy are considered. It is shown that for the Bethe-Salpeter equation, which takes into account the existence of the Fermi surface, there is a discrete spectrum in the system of two electrons. This phenomenon does not appear in the case of the Schr\"odinger equation.

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A. I. Milstein, I. S. Terekhov. 2025-03-24. Discrete spectrum of edge states in a two-dimensional topological insulator. https://arxiv.org/abs/2503.18390

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