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arXiv · 2602.19438

Excitonic pattern formation from a wrinkling instability in a van der Waals heterostructure

Zhiwen Zhou·L. H. Fowler-Gerace·W. J. Brunner·E. A. Szwed·Michael M. Fogler·Daniel E. Parker·L. V. Butov
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Abstract

We studied photoluminescence of spatially indirect excitons (IXs) in a MoSe$_2$/WSe$_2$ van der Waals heterostructure. We observed a quasi-periodic triangular pattern of IXs with a characteristic spatial wavelength $\sim{}2.6\,\mu\mathrm{m}$. Our theoretical analysis using a F\"oppl-von K\'arm\'an theory finds an elastic instability that produces triangular patterns with micrometer-scale wavelengths. This mechanism is consistent with the wavelength, symmetry, excitation power dependence, and temperature dependence of the observed IX pattern.

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Zhiwen Zhou, L. H. Fowler-Gerace, W. J. Brunner, E. A. Szwed, Michael M. Fogler, Daniel E. Parker, L. V. Butov. 2026-02-23. Excitonic pattern formation from a wrinkling instability in a van der Waals heterostructure. https://arxiv.org/abs/2602.19438

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