Correlatively Dependent Lattice and Electronic Structural Evolutions in Compressed Monolayer Tungsten Disulfide.
Transition-metal dichalcogenides (TMDs) are promising materials for optoelectronic devices. Their lattice and electronic structural evolutions under high strain conditions and their relations remain open questions. We exert pressure on WS2monolayers on different substrates, namely, Si/SiO2substrate and diamond anvil surface up to ∼25 GPa. Structural distortions in various degree are disclosed based on the emergence of Raman-inactive B mode. Splits of out-of-plane B and A1' modes are only observed on Si/SiO2substrate due to extra strain imported from volume decrease in Si and corrugation of SiO2surface, and its photoluminescence (PL) quenches quickly because of decreased K-K transition by conspicuous distortion of Brillouin zone. While diamond anvil surface provides better hydrostatic environment, combined analysis of PL and absorption proves that pressure effectively tunes PL emission energy and enhances Coulomb interactions. Knowledge of these distinct pressure tunable characteristics of monolayer WS2improves further understanding of structural and optical properties of TMDs.
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Bo
B
Han
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Fangfei
http://orcid.org/0000-0002-0342-3872
F
Li
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Liang
L
Li
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Xiaoli
X
Huang
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Yuanbo
Y
Gong
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Xinpeng
X
Fu
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Hanxue
H
Gao
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Qiang
Q
Zhou
State Key Laboratory of Superhard Materials, College of Physics, Jilin University , Changchun 130012, China.
Tian
http://orcid.org/0000-0002-9664-848X
T
Cui