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arXiv · 2512.08588

Anisotropic transport in ballistic bilayer graphene cavities

Abstract

Closing the gap between ray tracing simulations and experimentally observed electron jetting in bilayer graphene (BLG), we study all-electronic, gate-defined BLG cavities using tight-binding simulations and semiclassical equations of motion. Such cavities offer a rich playground to investigate anisotropic electron transport due to the trigonally warped Fermi surfaces. In this work, we achieve two things: First, we verify the existence of triangular modes (as predicted by classical ray tracing calculations) in the quantum solutions of closed circular BLG cavities. Then, we explore signatures of said triangular modes in transport through open BLG cavities connected to leads. We show that the triangular symmetry translates into anisotropic transport and present an optimal setup for experimental detection of the triangular modes as well as for controlled modulation of transport in preferred directions.

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Florian Schoeppl, Alina Mrenca-Kolasinska, Ming-Hao Liu, Korbinian Schwarzmaier, Klaus Richter, Angelika Knothe. 2025-12-09. Anisotropic transport in ballistic bilayer graphene cavities. https://arxiv.org/abs/2512.08588

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