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

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.