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arXiv · 2311.15052

Pseudomagnetic fields in fully relaxed twisted bilayer and trilayer graphene

Adrián Ceferino·Francisco Guinea
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Abstract

We present simple models to describe the in-plane and the out-of-plane lattice relaxation in twisted bilayer and symmetrically twisted trilayer graphene. Analytical results and series expansions show that for twist angles {\theta} > 1 $^{\circ}$, the in-plane atomic displacements lead to pseudomagnetic fields weakly dependent on {\theta}. In symmetrically twisted trilayer graphene, the central layer in-plane relaxation is greatly enhanced. The joint effect of the relaxation-induced pseudoscalar potentials and the associated energy difference between interlayer dimer and non-dimer pairs resulted in a significant electron-hole asymmetry both in twisted bilayer and trilayer graphene.

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Adrián Ceferino, Francisco Guinea. 2023-11-25. Pseudomagnetic fields in fully relaxed twisted bilayer and trilayer graphene. https://arxiv.org/abs/2311.15052

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