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arXiv · 2104.02720

Interactions-disorder duality and critical phenomena in nodal semimetals, dilute gases and other systems

Abstract

We investigate classes of interacting systems that allow for a mapping to disordered noninteracting systems. As we show, such a mapping is possible for interacting systems with a suppressed density of states at the chemical potential, leading to suppressed screening, and systems near BCS-type instabilities. The mapping can also be applied qualitatively to other classes of systems that are not exactly dual to each other. The established duality suggests a new approach to analytical and numerical studies of many-body and disorder-driven phenomena in a variety of systems and allows to predict, e.g., new phase transitions dual to the previously known ones. Using the established duality, we predict new disorder-driven transitions in nodal-line semimetals and systems with long-range hopping dual to, respectively, the BCS and BEC-vacuum transitions in interacting systems and new interaction-driven transitions dual to previously known non-Anderson disorder-driven transitions. The established principle can also be used to classify and describe phase transitions in dissipative systems described by non-Hermitian Hamiltonians.

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Shijun Sun, Sergey Syzranov. 2023-05-28. Interactions-disorder duality and critical phenomena in nodal semimetals, dilute gases and other systems. https://doi.org/10.1103/physrevb.108.195132

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