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arXiv · 2307.13336

Honeycomb anti-dot artificial lattice as a prototypical correlated Dirac fermions system

Andrzej Biborski·Michał Zegrodnik·Paweł Wójcik·Michał P. Nowak
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Abstract

We study theoretically the electronic properties of the artificial quantum dot honeycomb lattice defined in a two-dimensional electron gas, focusing on the possibility of achieving a regime in which electronic correlations play a dominant role. At first we establish a non-interacting model compatible with recently studied experimentally devices. According to the values of the obtained electron-electron interaction integrals, we postulate that the inclusion of inherent electron-gas self-screening is indispensable to reconstruct the experimental observations. Applying the Thomas-Fermi type of screening, we show that the radius of the anti-dot is crucial to achieve a correlated state in which phenomena like antiferromagentic ordering and interaction-induced insulating state appear. We estimate the conditions for which the electronically correlated state in an artificial honeycomb lattice can be realized.

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Andrzej Biborski, Michał Zegrodnik, Paweł Wójcik, Michał P. Nowak. 2023-07-25. Honeycomb anti-dot artificial lattice as a prototypical correlated Dirac fermions system. https://arxiv.org/abs/2307.13336

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