Probing topology in thin films with quantum Sondheimer oscillations

Léo Mangeolle; Johannes Knolle

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arXiv · 2604.10141

Probing topology in thin films with quantum Sondheimer oscillations

Léo Mangeolle·Johannes Knolle

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Abstract

Sondheimer oscillations (SO) are magnetoresistance oscillations occurring in thin films due to the commensurability between cyclotron motion and sample thickness, and are traditionally regarded as a purely semiclassical size effect. Here we develop a general quantum theory of SO for thin-film conductors in the quantum limit of a large magnetic field. We show that corrections arising from band topology modify the SO frequency, in contrast to Shubnikov-de Haas oscillations where topological information appears only in the phase. As a consequence, quantum SO provide a direct and robust probe of the full Landau level spectrum. Applying our framework to a minimal model with tunable Berry phase, we demonstrate how topology manifests itself in experimentally accessible magneto-oscillation spectra and discuss damping mechanisms including surface roughness.

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Léo Mangeolle, Johannes Knolle. 2026-04-11. Probing topology in thin films with quantum Sondheimer oscillations. https://arxiv.org/abs/2604.10141

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