Nitrogen doping induced metal-insulator transition with iso-symmetric character in rutile VO2

Baichen Lin; Shanquan Chen; Yubo Zhang; Yangyang Si; Haoliang Huang; Chuanrui Huo; Frans Munnik; Yongqi Dong; Lu You; Jian Shao; Yu-Chieh Ku; Nguyen Nhat Quyen; Aryan Keshri; Zhenlin Luo; Weiwei Zhao; Chun-Fu Chang; Chih-Wei Luo; Sujit Das; Shiqing Deng; Chang-Yang Kuo; Zuhuang Chen

arXiv · 2604.24240

Nitrogen doping induced metal-insulator transition with iso-symmetric character in rutile VO2

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Abstract

Metal-insulator transitions (MITs) in correlated oxides offer immense potential for next-generation Mottronic devices. However, their integration into practical applications is often hindered by the coupling of MITs with symmetry-lowering structural phase transitions, which limits switching speed and endurance. In this study, we engineered an iso-symmetric MIT on average in epitaxial rutile VO2 thin films via an in-situ nitrogen doping strategy. Nitrogen incorporation effectively suppresses V-V dimerization, enabling an iso-symmetric MIT, while preserving the original crystal symmetry. Furthermore, in-operando time-resolved optical reflectivity measurements revealed a shortened switching time in nitrogen-doped films, highlighting their enhanced performance. Our findings provide critical insights into the underlying mechanisms of MITs and introduce anion doping as a powerful tool for tailoring phase transitions in strongly correlated electron systems. This approach opens new avenues for the development of high-performance electronic and photonic devices.

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Baichen Lin, Shanquan Chen, Yubo Zhang, Yangyang Si, Haoliang Huang, Chuanrui Huo, Frans Munnik, Yongqi Dong, Lu You, Jian Shao, Yu-Chieh Ku, Nguyen Nhat Quyen, Aryan Keshri, Zhenlin Luo, Weiwei Zhao, Chun-Fu Chang, Chih-Wei Luo, Sujit Das, Shiqing Deng, Chang-Yang Kuo, Zuhuang Chen. 2026-04-27. Nitrogen doping induced metal-insulator transition with iso-symmetric character in rutile VO2. https://arxiv.org/abs/2604.24240

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