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arXiv · 2512.22480

Inverse scattering for waveguides in topological insulators

Guillaume Bal·Xixian Wang·Zhongjian Wang
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Abstract

This paper concerns the inverse scattering problem of a topologically non-trivial waveguide separating two-dimensional topological insulators. We consider the specific model of a Dirac system. We show that a short-range perturbation can be fully reconstructed from scattering data in a linearized setting and in a finite-dimensional setting under a smallness constraint. We also provide a stability result in appropriate topologies. We then solve the problem numerically by means of a standard adjoint method and illustrate our theoretical findings with several numerical simulations.

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Guillaume Bal, Xixian Wang, Zhongjian Wang. 2025-12-27. Inverse scattering for waveguides in topological insulators. https://arxiv.org/abs/2512.22480

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