中国物理B ›› 2023, Vol. 32 ›› Issue (6): 67103-067103.doi: 10.1088/1674-1056/acc7f9
Zilu Wang(王子禄)1,2, Haoyu Dong(董皓宇)1,2, Weichang Zhou(周伟昌)3,†, Zhihai Cheng(程志海)1,2,‡, and Shancai Wang(王善才)1,2,§
Zilu Wang(王子禄)1,2, Haoyu Dong(董皓宇)1,2, Weichang Zhou(周伟昌)3,†, Zhihai Cheng(程志海)1,2,‡, and Shancai Wang(王善才)1,2,§
摘要: Layered transition metal dichalcogenides (TMDCs) gained widespread attention because of their electron-correlation-related physics, such as charge density wave (CDW), superconductivity, etc. In this paper, we report the high-resolution angle-resolved photoemission spectroscopy (ARPES) studies on the electronic structure of Ti-doped $1T$-Ti$_x$Ta$_{1-x}$S$_2$ with different doping levels. We observe a flat band that originates from the formation of the star of David super-cell at the $x=5$% sample at the low temperature. With the increasing Ti doping levels, the flat band vanishes in the $x=8$% sample due to the extra hole carrier. We also find the band shift and variation of the CDW gap caused by the Ti-doping. Meanwhile, the band folding positions and the CDW vector $\bm q_{{\rm{CDW}}}$ are intact. Our ARPES results suggest that the localized flat band and the correlation effect in the $1T$-TMDCs could be tuned by changing the filling factor through the doping electron or hole carriers. The Ti-doped $1T$-Ti$_x$Ta$_{1-x}$S$_2$ provides a platform to fine-tune the electronic structure evolution and a new insight into the strongly correlated physics in the TMDC materials.
中图分类号: (Electron density of states and band structure of crystalline solids)