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arXiv · 2606.06466

Enhancement of charge correlations and real-space topological marker on an interacting non-Hermitian Su-Schrieffer-Heeger model

Sebastião dos A. Sousa-Júnior·Pedro B. Melo·Rubem Mondaini·Arnob Kumar Ghosh·Rodrigo Arouca
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Abstract

We investigate the interacting non-Hermitian Su-Schrieffer-Heeger (SSH) model, focusing on the interplay between topology and charge ordering. Using a real-space topological marker, charge correlations, and the complex many-body spectrum, we map out the phase diagram under periodic and open boundary conditions. We show that the topological marker remains a robust diagnostic of non-Hermitian topological phases in the presence of interactions and consistently signals their breakdown at the onset of a charge density wave (CDW). We further demonstrate that non-Hermiticity enhances interaction effects: While moderate changes occur under periodic boundary conditions, open boundary conditions lead to a pronounced amplification of staggered charge correlations near exceptional points. This enhancement arises from the accumulation of low-energy states near exceptional points, which promotes electronic instabilities and strengthens CDW tendencies.

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Sebastião dos A. Sousa-Júnior, Pedro B. Melo, Rubem Mondaini, Arnob Kumar Ghosh, Rodrigo Arouca. 2026-06-04. Enhancement of charge correlations and real-space topological marker on an interacting non-Hermitian Su-Schrieffer-Heeger model. https://arxiv.org/abs/2606.06466

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