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arXiv · 2103.12079

Dynamically Induced Exceptional Phases in Quenched Interacting Semimetals

Carl Lehmann·Michael Schüler·Jan Carl Budich
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Abstract

We report on the dynamical formation of exceptional degeneracies in basic correlation functions of non-integrable one- and two-dimensional systems quenched to the vicinity of a critical point. Remarkably, fine-tuned semi-metallic points in the phase diagram of the considered systems are thereby promoted to topologically robust non-Hermitian (NH) nodal phases emerging in the coherent long-time evolution of a dynamically equilibrating system. In the framework of non-equilibrium Green's function methods within the conserving second Born approximation, we predict observable signatures of these novel NH nodal phases in simple spectral functions as well as in the time-evolution of momentum distribution functions.

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Carl Lehmann, Michael Schüler, Jan Carl Budich. 2021-03-22. Dynamically Induced Exceptional Phases in Quenched Interacting Semimetals. https://doi.org/10.1103/physrevlett.127.106601

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