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arXiv · 2508.21359

Tunable Two-Dimensional Electron Gas at the Interfaces of Ferroelectric Potassium Tantalate Niobates

Jiaxin Lv·Silan Li·Chenhao Duan·Shuanhu Wang·Hong Yan·Kexin Jin
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Abstract

The heterointerfaces at complex oxides have emerged as a promising platform for discovering novel physical phenomena and advancing integrated sensing, storage, and computing technologies. Nevertheless, achieving precise control over a two-dimensional electron gas (2DEG) in a ferroelectric oxide-based field-effect transistor (FET) configuration remains challenging. Here, we firstly demonstrate a tunable 2DEG system fabricated by depositing an amorphous LaAlO3(LAO) film onto a (001)-oriented ferroelectric potassium tantalate niobate substrate. Interfaces grown under high-temperature and high-oxygen-pressure conditions exhibit a good metallic conduction. Notably, well-defined metallic 2DEGs displaying pronounced hysteresis and persistent electric-field-modulated resistance are observed below 108 K, achieving a resistance modulation of 11.6% at 7 K. These results underscore the potential for extending such behavior to other oxide-based 2DEG systems and facilitate further exploration of ferroelectric metals in complex oxide heterostructures.

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Jiaxin Lv, Silan Li, Chenhao Duan, Shuanhu Wang, Hong Yan, Kexin Jin. 2025-08-29. Tunable Two-Dimensional Electron Gas at the Interfaces of Ferroelectric Potassium Tantalate Niobates. https://arxiv.org/abs/2508.21359

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