Pseudogap and Weak Multifractality in 2D Disordered Mott Charge-Density-Wave Insulator

被引:10
作者
Gao, Jianhua [1 ]
Park, Jae Whan [1 ]
Kim, Kiseok [2 ]
Song, Sun Kyu [1 ,2 ]
Park, Hae Ryong [1 ,2 ]
Lee, Jhinhwan [1 ]
Park, Jewook [1 ]
Chen, Fangchu [3 ,4 ]
Luo, Xuan [3 ]
Sun, Yuping [3 ,5 ,6 ]
Yeom, Han Woong [1 ,2 ]
机构
[1] Inst Basic Sci IBS, Ctr Artificial Low Dimens Elect Syst, Pohang 37673, South Korea
[2] Pohang Univ Sci & Technol, Dept Phys, Pohang 37673, South Korea
[3] Chinese Acad Sci, Inst Solid State Phys, Key Lab Mat Phys, Hefei 230031, Peoples R China
[4] Univ Sci & Technol China, Hefei 230026, Peoples R China
[5] Chinese Acad Sci, High Magnet Field Lab, Hefei 230031, Peoples R China
[6] Nanjing Univ, Collaborat Innovat Ctr Adv Microstruct, Nanjing 210093, Peoples R China
基金
中国国家自然科学基金;
关键词
charge density wave; Mott insulator; transition metal dichalcogenide; pseudogap; multifractality; disorder; SUPERCONDUCTIVITY; PHASE; TRANSITION; 1T-TAS2; STATE;
D O I
10.1021/acs.nanolett.0c01607
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
We investigate electronic states of Se-substituted 1T-TaS2 by scanning tunneling microscopy/spectroscopy (STM/STS), where superconductivity emerges from the unique Mott-charge-density-wave (Mott-CDW) state. Spatially resolved STS measurements reveal that a pseudogap replaces the Mott gap with the CDW gaps intact. The pseudogap has little correlation with the unit-cell-to-unit-cell variation in the local Se concentration but appears globally. The correlation length of the local density of states (LDOS) is substantially enhanced at the Fermi energy and decays rapidly at high energies. Furthermore, the statistical analysis of LDOS indicates the weak multifractal behavior of the wave functions. These findings suggest a correlated metallic state induced by disorder and provide a new insight into the emerging superconductivity in two-dimensional materials.
引用
收藏
页码:6299 / 6305
页数:7
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