Flat-Band Generation in InAs/GaSb Quantum Wells through Vertically Engineered Heterostructures

Zachery A. Enderson; Jiyuan Fang; Wei-Chen Wang; Li Xiang; Mykhaylo Ozerov; Dmitry Smirnov; Zhigang Jiang; Samuel D. Hawkins; Aaron J. Muhowski; John F. Klem; Wei Pan

arXiv · 2603.15593

Flat-Band Generation in InAs/GaSb Quantum Wells through Vertically Engineered Heterostructures

Zachery A. Enderson·Jiyuan Fang·Wei-Chen Wang·Li Xiang·Mykhaylo Ozerov·Dmitry Smirnov·Zhigang Jiang·Samuel D. Hawkins·Aaron J. Muhowski·John F. Klem·Wei Pan

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Abstract

Quantum materials constitute a novel category of substances wherein quantum effects and electron-electron (e-e) interactions give rise to unforeseen phenomena on a macroscopic scale. Of particular interest within the realm of quantum materials are flat bands, which promote heavy conduction electrons and enhance e-e correlation effects. While the engineering of such flat bands has been demonstrated in graphene and two-dimensional transition metal dichalcogenides moir\'e superlattices and in lithography defined semiconductor moir\'e superlattices, conventional tear-and-stack fabrication methods face challenges due to inevitable twist-angle disorder, strain, and relaxation effects, leading to issues with reproducibility and scalability. Here, we explore the creation and modification of flat bands through vertically engineered III-V semiconductor heterostructures, without the need for twisting. These artificial quantum materials offer a reproducible and scalable means for producing high-quality flat-band materials via molecular beam epitaxy growth. Our investigation includes magnetotransport and infrared magneto-spectroscopy studies of quad-layer InAs/GaSb quantum wells, accompanied by k*p band structure calculations, which illustrate the flattening of bands in vertically designed heterostructures.

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Zachery A. Enderson, Jiyuan Fang, Wei-Chen Wang, Li Xiang, Mykhaylo Ozerov, Dmitry Smirnov, Zhigang Jiang, Samuel D. Hawkins, Aaron J. Muhowski, John F. Klem, Wei Pan. 2026-03-16. Flat-Band Generation in InAs/GaSb Quantum Wells through Vertically Engineered Heterostructures. https://arxiv.org/abs/2603.15593

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