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arXiv · 2406.08576

Laser induced $\mathcal{PT}$-symmetry breaking in the fluctuations of electronic fluids

Rui Aquino·Nathan O. Silvano·Daniel G. Barci
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Abstract

Electronic fluids can display exciting dynamical properties. In particular, due to Landau damping, the collective modes spectrum of an electronic system with multipolar interactions is non-hermitian, and can present non-hermitian degeneracies called $\textit{exceptional points}$. In this work, we want to explore the dynamical properties of these degeneracies using laser control. We show that by using a light pulse, we can control the collective mode spectrum and tune a non-hermitian $\mathcal{PT}$ phase transition in which two exceptional points anhilate each other. At this transition, the gap closes with a cubic root signature, what defines a third order exceptional point.

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Rui Aquino, Nathan O. Silvano, Daniel G. Barci. 2024-06-12. Laser induced $\mathcal{PT}$-symmetry breaking in the fluctuations of electronic fluids. https://doi.org/10.1103/physrevb.110.085147

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