Two-Dimensional Superconductivity at the Titanium Sesquioxide Heterointerface

Lijie Wang; Wenhao He; Guangyi Huang; Huanyi Xue; Guanqun Zhang; Gang Mu; Shiwei Wu; Zhenghua An; Changlin Zheng; Yan Chen; Wei Li

doi:10.1021/acsnano.2c04795

arXiv · 2106.06948

Two-Dimensional Superconductivity at the Titanium Sesquioxide Heterointerface

Lijie Wang·Wenhao He·Guangyi Huang·Huanyi Xue·Guanqun Zhang·Gang Mu·Shiwei Wu·Zhenghua An·Changlin Zheng·Yan Chen·Wei Li

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Abstract

The study of exotic superconductivity in two dimensions has been a central theme in solid state and materials research communities. Experimentally exploring and identifying new fascinating interface superconductors with a high transition temperature ($T_c$) is challenging. Here, we report an experimental observation of intriguing two-dimensional superconductivity with a $T_c$ up to 3.8 K at the interface between Mott insulator Ti$_2$O$_3$ and polar semiconductor GaN. At the verge of superconductivity, we also observe a striking quantum metallic-like state, demonstrating that it is a precursor to the two-dimensional superconductivity as the temperature is decreased. Our work is the first time finding this intriguing superconducting state at the heterointerface, which not only brings a new broad of perspective on the emergent quantum phenomena at the heterointerfaces but also sheds new light on exploiting the novel heterointerface superconductivity with high-$T_c$ via heterostructure engineering.

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Lijie Wang, Wenhao He, Guangyi Huang, Huanyi Xue, Guanqun Zhang, Gang Mu, Shiwei Wu, Zhenghua An, Changlin Zheng, Yan Chen, Wei Li. 2021-06-13. Two-Dimensional Superconductivity at the Titanium Sesquioxide Heterointerface. https://doi.org/10.1021/acsnano.2c04795

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