Growth, characterization, and Raman spectra of the 1T phases of TiTe_(2), TiSe_(2), and TiS_(2)

作     者：唐筱芳 朱双兴 刘豪 章晨 吴旗仪 刘子腾 宋姣姣 郭晓 王永松 马赫 赵尹陬 邬钒颖 刘姝妤 刘开辉 袁亚华 黄寒 何军 徐文 刘海云 段玉霞 孟建桥 Xiao-Fang Tang;Shuang-Xing Zhu;Hao Liu;Chen Zhang;Qi-Yi Wu;Zi-Teng Liu;Jiao-Jiao Song;Xiao Guo;Yong-Song Wang;He Ma;Yin-Zou Zhao;Fan-Ying Wu;Shu-Yu Liu;Kai-Hui Liu;Ya-Hua Yuan;Han Huang;Jun He;Wen Xu;Hai-Yun Liu;Yu-Xia Duan;Jian-Qiao Meng

作者机构：Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of SciencesHefei 230031China University of Science and Technology of ChinaHefei 230026China School of Physics and Electronics Central South UniversityChangsha 410083China State Key Laboratory for Mesoscopic Physics Collaborative Innovation Center of Quantum MatterSchool of Physics Peking UniversityBeijing 100871China Beijing Academy of Quantum Information SciencesBeijig 10085China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2022年第31卷第3期

页      面：482-487页

核心收录：

学科分类：081702[工学-化学工艺] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070302[理学-分析化学] 0703[理学-化学] 

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 12074436 and U1930116) the Innovation-driven Plan in Central South University (Grant No. 2016CXS032) 

主　　题：transition-metal dichalcogenides chemical vapor transport Raman phonon 

摘      要：High-quality large 1T phase of TiX_(2)(X = Te, Se, and S) single crystals have been grown by chemical vapor transport using iodine as a transport agent. The samples are characterized by compositional and structural analyses, and their properties are investigated by Raman spectroscopy. Several phonon modes have been observed, including the widely reported A_(1g) and E_(8) modes, the rarely reported E_(u) mode(-83 cm^(-1) for TiTe_(2), and -185 cm^(-1)for TiS_(2)), and even the unexpected K mode(-85 cm^(-1)) of TiTe_(2). Most phonons harden with the decrease of temperature, except that the K mode of TiTe_(2) and the E_(u) and “A_(2u)/Sh modes of TiS_(2) soften with the decrease of temperature. In addition, we also found phonon changes in TiSe_(2) that may be related to charge density wave phase transition. Our results on TiX_(2) phonons will help to understand their charge density wave and superconductivity.