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arXiv · 2111.10156

Quasi-stationary near-gate plasmons in van der Waals heterostructures

A. A. Zabolotnykh·V. V. Enaldiev·V. A. Volkov
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Abstract

Near-gate plasmons are a new type of plasma oscillations emerging in homogeneous two-dimensional electron systems where a gate provides partial screening of electron-electron interaction. Here we develop a theory of the near-gate plasmons in van der Waals heterostructures comprising a conducting layer separated by a thin insulator from an uncharged disk-shaped gate. We show that in these structures the near-gate plasmons form gate-size-quantized quasi-stationary discrete modes even in the collisionless limit. Belonging to continuum spectrum of two-dimensional plasmons outside of the disk-gate, the near-gate plasmons are manifested as Fano-like resonances in frequency and magnetodispersions of scattering cross-section of the former scattered off the region under the gate. This enables to recover spectrum of the near-gate plasmons in the van der Waals heterostructures using near-field imaging techniques.

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A. A. Zabolotnykh, V. V. Enaldiev, V. A. Volkov. 2021-12-02. Quasi-stationary near-gate plasmons in van der Waals heterostructures. https://doi.org/10.1103/physrevb.104.195435

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