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arXiv · 2002.06570

Non-Hermitian CT-Symmetric Spectral Protection of Nonlinear Defect Modes

Do Hyeok Jeon·Mattis Reisner·Fabrice Mortessagne·Tsampikos Kottos·Ulrich Kuhl
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Abstract

We investigate, using a microwave platform consisting of a non-Hermitian Su-Schrieffer-Heeger array of coupled dielectric resonators, the interplay of a lossy nonlinearity and CT-symmetry in the formation of defect modes. The measurements agree with the theory which predicts that, up to moderate pumping, the defect mode is an eigenstate of the CT-symmetric operator and retains its frequency at the center of the gap. At higher pumping values, the system undergoes a self-induced explicit \CT-symmetry violation which removes the spectral topological protection and alters the shape of the defect mode.

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Do Hyeok Jeon, Mattis Reisner, Fabrice Mortessagne, Tsampikos Kottos, Ulrich Kuhl. 2020-02-16. Non-Hermitian CT-Symmetric Spectral Protection of Nonlinear Defect Modes. https://doi.org/10.1103/physrevlett.125.113901

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