Electronic structure of superconducting VN(111) films

Rongjing Zhai; Jiachang Bi; Shun Zheng; Wei Chen; Yu Lin; Shaozhu Xiao; Yanwei Cao

doi:10.1186/s11671-024-03978-x

Electronic structure of superconducting VN(111) films

Discov Nano. 2024 Mar 11;19(1):42. doi: 10.1186/s11671-024-03978-x.

Authors

Rongjing Zhai^{1

2}, Jiachang Bi³, Shun Zheng⁴, Wei Chen⁵, Yu Lin^{1

6}, Shaozhu Xiao^{1

6}, Yanwei Cao^{7

8}

Affiliations

¹ Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
² University of Science and Technology of China, Hefei, 230026, China.
³ Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China. bijiachang@nimte.ac.cn.
⁴ State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China.
⁵ Hefei Innovation Research Institute, Beihang University, Hefei, 230013, China.
⁶ Yongjiang Laboratory, Ningbo, 315202, Zhejiang, China.
⁷ Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China. ywcao@nimte.ac.cn.
⁸ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China. ywcao@nimte.ac.cn.

Abstract

Vanadium nitride (VN) is a transition-metal nitride with remarkable properties that have prompted extensive experimental and theoretical investigations in recent years. However, there is a current paucity of experimental research investigating the temperature-dependent electronic structure of single-crystalline VN. In this study, high-quality VN(111) films were successfully synthesized on $α$ -Al $_{2}$ O $_{3}$ (0001) substrates using magnetron sputtering. The crystal and electronic structures of the VN films were characterized by a combination of high-resolution X-ray diffraction, low-energy electron diffraction, resonant soft X-ray absorption spectroscopy, and ultraviolet photoelectron spectroscopy. The electrical transport measurements indicate that the superconducting critical temperature of the VN films is around 8.1 K. Intriguingly, the temperature-dependent photoelectron spectroscopy measurements demonstrate a weak temperature dependence in the electronic structure of the VN films, which is significant for understanding the ground state of VN compounds.

Keywords: Electronic structure; Epitaxy; Superconductivity; Vanadium nitride.

Grants and funding

No. 2022YFA1403000/National Key Research and Development Program of China