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arXiv · 2312.02423

The rise and fall of the amplitude, and phase, around Exceptional Points: a Scattering matrix approach

J. Colín-Gálvez·E. Castaño·G. Báez·V. Domínguez-Rocha
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Abstract

We analyze the behavior of a non-Hermitian opened one-dimensional quantum system with $\mathcal{PT}$ symmetry. This system is built by a dimer, with balanced gains and losses described by a parameter $\gamma$. By varying $\gamma$ the system resonances, which are naturally separated, coalesce at the exceptional point (EP). The transmission spectrum is obtained by means of the scattering matrix ($S$ matrix) formalism and we examine the wave functions corresponding to the resonances as a function of $\gamma$. Specifically, we look for the behavior and distribution of the phases of the $S$ matrix before, at and after the EP.

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J. Colín-Gálvez, E. Castaño, G. Báez, V. Domínguez-Rocha. 2023-12-05. The rise and fall of the amplitude, and phase, around Exceptional Points: a Scattering matrix approach. https://arxiv.org/abs/2312.02423

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