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arXiv · 2505.09735

A Mobile Impurity in the Kitaev Chain: Phase Diagram and Signatures of Topology

A. V. Sadovnikov·M. S. Bahovadinov·A. N. Rubtsov·A. A. Markov
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Abstract

We study the physics of a mobile impurity immersed in a $1d$ topological superconductor. We discuss the system's phase diagram obtained with exact diagonalization. We argue that the character of the transition from a weak to strong coupling regime depends on the phase of the host superconductor. A smooth crossover between a weakly coupled polaron and a molecular state is observed in the topological phase. In contrast, the impurity undergoes a sharp phase transition in a topologically trivial background.

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A. V. Sadovnikov, M. S. Bahovadinov, A. N. Rubtsov, A. A. Markov. 2025-05-14. A Mobile Impurity in the Kitaev Chain: Phase Diagram and Signatures of Topology. https://arxiv.org/abs/2505.09735

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