Fourth-order exceptional points in correlated quantum many-body systems
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Non-Hermtian (NH) Hamiltonians effectively describing the physics of dissipative systems have become an important tool with applications ranging from classical metamaterials to quantum many-body systems. Exceptional points, the NH counterpart of spectral degeneracies, are among the paramount phenomena unique to the NH realm. While realizations of second-order exceptional points have been reported in a variety of microscopic models, higher-order ones have largely remained elusive in the many-body context, as they in general require fine tuning in high-dimensional parameter spaces. Here, we propose a microscopic model of correlated fermions in three spatial dimensions and demonstrate the occurrence of interaction-induced fourth-order exceptional points that are protected by chiral symmetry. We demonstrate their stability against symmetry-breaking perturbations and investigate their characteristic analytical and topological properties.
Details
Original language | English |
---|---|
Article number | L121109 |
Journal | Physical Review B |
Volume | 104 |
Issue number | 12 |
Publication status | Published - 15 Sept 2021 |
Peer-reviewed | Yes |