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.
作者
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
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(Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China;School of Physics and Electronics Central South University,Changsha 410083,China;State Key Laboratory for Mesoscopic Physics Collaborative Innovation Center of Quantum Matter,School of Physics Peking University,Beijing 100871,China;Beijing Academy of Quantum Information Sciences,Beijig 10085,China)
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)。
