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arXiv · 2411.03748

First order Quantum Hall to Wigner crystal phase transition on a triangular lattice: an iDMRG study

Gleb Fedorovich·Clemens Kuhlenkamp·Atac Imamoglu·Ivan Amelio
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Abstract

In this work we study a system of interacting fermions on a triangular lattice in the presence of an external magnetic field. We neglect spin and fix a density of one third, with one unit of magnetic flux per particle. The infinite density matrix renormalization group algorithm is used to compute the ground state of this generalized Fermi-Hubbard model. Increasing the strength of the nearest-neighbor repulsion, we find a first order transition between an Integer Quantum Hall phase and a crystalline, generalized Wigner crystal state. The first-order nature of the phase transition is consistent with a Ginzburg-Landau argument. We expect our results to be relevant for moir\'e heterostructures of two-dimensional materials.

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Gleb Fedorovich, Clemens Kuhlenkamp, Atac Imamoglu, Ivan Amelio. 2024-11-06. First order Quantum Hall to Wigner crystal phase transition on a triangular lattice: an iDMRG study. https://arxiv.org/abs/2411.03748

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