Decorated electronic kagome lattice in twisted bilayer germanene

Dennis J. Klaassen; Rian A. M. Ligthart; Andrés R. Botello Mendez; Lumen Eek; Esra van 't Westende; Paul L. de Boeij; Y. Wang; D. Vanmaekelbergh; Pantelis Bampoulis; Cristiane Morais Smith; Ingmar Swart; Zeila Zanolli; Harold J. W. Zandvliet

arXiv · 2609.08750

Decorated electronic kagome lattice in twisted bilayer germanene

Dennis J. Klaassen·Rian A. M. Ligthart·Andrés R. Botello Mendez·Lumen Eek·Esra van 't Westende·Paul L. de Boeij·Y. Wang·D. Vanmaekelbergh·Pantelis Bampoulis·Cristiane Morais Smith·Ingmar Swart·Zeila Zanolli·Harold J. W. Zandvliet

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Abstract

Artificial kagome lattices provide a route to electronic flat bands, geometric frustration, and correlation driven phases, but their realization in atomically controlled two-dimensional materials remains scarce. Here, we show that commensurate twisted bilayer germanene on Ge2Pt produces two electronically distinct large-angle moir\'e phases. Scanning tunneling microscopy measurements and density functional theory calculations reveal that commensurate twisted bilayers that are odd under an exchange of sublattices are semiconducting, whereas the twisted bilayers with an even parity are metallic. The twisted bilayers with an even parity host an empty state resonance that exhibits an emergent decorated kagome structure with a C3 symmetry. These results establish large-angle twisted germanene as a platform for engineering kagome-like electronic states in a buckled two-dimensional material.

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Dennis J. Klaassen, Rian A. M. Ligthart, Andrés R. Botello Mendez, Lumen Eek, Esra van 't Westende, Paul L. de Boeij, Y. Wang, D. Vanmaekelbergh, Pantelis Bampoulis, Cristiane Morais Smith, Ingmar Swart, Zeila Zanolli, Harold J. W. Zandvliet. 2026-09-08. Decorated electronic kagome lattice in twisted bilayer germanene. https://arxiv.org/abs/2609.08750

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