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arXiv · 2606.24670

Simulating the Haldane model in ultra-clean GaAs heterostructures

Francesco Cioni·Lorenzo Cavicchi·Fabio Taddei·Marco Polini
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Abstract

The Haldane model represents the minimal lattice-based realization of a Chern insulator, exhibiting a quantized Hall conductance in the absence of Landau levels. Despite its conceptual elegance, the implementation in crystalline solids of the requisite pattern of Peierls phases breaking time-reversal symmetry remains experimentally demanding. In this work, we theoretically investigate the possibility to simulate the Haldane model in ultra-clean GaAs/AlGaAs heterostructures. Our proposal relies on recent experiments in which a high-mobility two-dimensional electron gas is subject to a gate-defined honeycomb electrostatic potential and a laterally periodic magnetic field generated by patterned ferromagnetic structures. The combined electrostatic and magnetic superlattices furnish a viable route to emulate the topological properties of the Haldane model.

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Francesco Cioni, Lorenzo Cavicchi, Fabio Taddei, Marco Polini. 2026-06-23. Simulating the Haldane model in ultra-clean GaAs heterostructures. https://arxiv.org/abs/2606.24670

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