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arXiv · 2601.17402

Tunable two-dimensional Dirac-Weyl semimetal phase induced by altermagnetism

Lizhou Liu·Qing-Feng Sun·Ying-Tao Zhang
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Abstract

We demonstrate a tunable Dirac-Weyl semimetal phase in two dimensions, realized by introducing in-plane d-wave altermagnetism into a Dirac system. This phase hosts both a central Dirac point and momentumseparated Weyl points connected by Fermi line edge states. The Weyl point positions--and thus the edge-state connectivity--can be continuously tuned by rotating the altermagnetic axis. In contrast, out-of-plane altermagnetism gaps part of the bulk spectrum while preserving a single Dirac point accompanied by chiral edge modes, as evidenced by quantized edge polarization. Our findings provide a tunable platform for manipulating Dirac-Weyl physics and topological edge transport in two dimensions.

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Lizhou Liu, Qing-Feng Sun, Ying-Tao Zhang. 2026-01-24. Tunable two-dimensional Dirac-Weyl semimetal phase induced by altermagnetism. https://doi.org/10.1103/3hxt-fynf

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