Non-Hermitian topology and skin modes in the continuum via parametric processes

Markus Bestler; Alexander Dikopoltsev; Oded Zilberberg

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arXiv · 2505.02776

Non-Hermitian topology and skin modes in the continuum via parametric processes

Markus Bestler·Alexander Dikopoltsev·Oded Zilberberg

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Abstract

We demonstrate that Hermitian, nonlocal parametric pairing processes can induce non-Hermitian topology and skin modes, offering a simple alternative to complex bath engineering. Our model, stabilized by local dissipation and operating in the continuum limit, reveals exceptional points that spawn a tilted diabolical line in the dispersion. Local dissipation prevents instabilities, while a bulk anomaly signals unscreened current response. Upon opening the boundaries, we observe a non-Hermitian skin effect with localized edge modes. Through bulk winding indices and non-Bloch theory, we establish a robust bulk-boundary correspondence, highlighting parametric drives as a scalable route to non-Hermitian topology in bosonic systems.

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Markus Bestler, Alexander Dikopoltsev, Oded Zilberberg. 2025-05-05. Non-Hermitian topology and skin modes in the continuum via parametric processes. https://arxiv.org/abs/2505.02776

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