Open AccessAnisotropic Collective Charge Excitations in Quasimetallic 2D Transition‐Metal Dichalcogenides
Author(s) -
Tang Chi Sin,
Yin Xinmao,
Yang Ming,
Wu Di,
Wu Jing,
Wong Lai Mun,
Li Changjian,
Tong Shi Wun,
Chang YungHuang,
Ouyang Fangping,
Feng Yuan Ping,
Wang Shi Jie,
Chi Dongzhi,
Breese Mark B. H.,
Zhang Wenjing,
Rusydi Andrivo,
Wee Andrew T. S.
Publication year - 2020
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201902726
Subject(s) - condensed matter physics , quasiparticle , charge (physics) , plasmon , monolayer , anisotropy , superconductivity , coupling (piping) , zigzag , charge ordering , phase transition , phase (matter) , transition metal , materials science , physics , nanotechnology , chemistry , optoelectronics , optics , quantum mechanics , biochemistry , geometry , mathematics , metallurgy , catalysis
The quasimetallic 1T′ phase 2D transition‐metal dichalcogenides (TMDs) consist of 1D zigzag metal chains stacked periodically along a single axis. This gives rise to its prominent physical properties which promises the onset of novel physical phenomena and applications. Here, the in‐plane electronic correlations are explored, and new mid‐infrared plasmon excitations in 1T′ phase monolayer WSe 2 and MoS 2 are observed using optical spectroscopies. Based on an extensive first‐principles study which analyzes the charge dynamics across multiple axes of the atomic‐layered systems, the collective charge excitations are found to disperse only along the direction perpendicular to the chains. Further analysis reveals that the interchain long‐range coupling is responsible for the coherent 1D charge dynamics and the spin–orbit coupling affects the plasmon frequency. Detailed investigation of these charge collective modes in 2D‐chained systems offers opportunities for novel device applications and has implications for the underlying mechanism that governs superconductivity in 2D TMD systems.