Topological properties of a chain of interacting electrons

Igor N. Karnaukhov; E. E. Krasovskii

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arXiv · 2505.06733

Topological properties of a chain of interacting electrons

Igor N. Karnaukhov·E. E. Krasovskii

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Abstract

Within the framework of a one-dimensional model of interacting electrons, the ground state of an electron liquid is studied. Using the exact solution of the model, the ground state phase diagram and zero-energy Majorana edge functions in a finite chain are calculated. The winding number invariant reflects the topological nature of the electron liquid. The phase diagram includes two topological phases with different winding number invariants, the topologically trivial Mott insulator phase, and three critical phase transition points. Numerical calculations confirm and illustrate the analytical results.

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Igor N. Karnaukhov, E. E. Krasovskii. 2025-05-10. Topological properties of a chain of interacting electrons. https://arxiv.org/abs/2505.06733

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