Controlled growth of 3R phase tantalum diselenide and its enhanced superconductivity

• Main Authors: Deng, Ya, Lai, Yuanming, Zhao, Xiaoxu, Wang, Xiaowei, Zhu, Chao, Huang, Ke, Zhou, Jiadong, Zeng, Qingsheng, Duan, Ruihuan, Fu, Qundong, Kang, Lixing, Liu, Yang, Pennycook, Stephen J., Wang, Renshaw Xiao, Liu, Zheng
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2021
• Subjects: Engineering::Materials; Crystals; Superconducting Transition
• Online Access: https://hdl.handle.net/10356/151387
• Institution: Nanyang Technological University

Transition metal dichalcogenides (TMDs) have become a playground for exploring rich physical phenomena like superconductivity and charge-density-waves (CDW). Here, we report the synthesis of the atom-thin TaSe2 with a rare 3R phase and enhanced superconductivity. The 3R phase is achieved by an ambient pressure chemical vapor deposition (CVD) strategy and confirmed by the high-resolution aberration-corrected STEM. Low-temperature transport data reveal an enhanced superconducting transition temperature (Tc) of 1.6 K in the 3R-TaSe2, which undoubtedly breaks the traditional perception of TaSe2 crystal as a material with Tc close to 0 K. This work demonstrates the strength of ambient pressure CVD in the exploration of crystal polymorphism, highlights a decisive role of layer stacking order in the superconducting transition, and provides fresh insights on manipulating crystal structures to gain access to enhanced Tc.