Composition dependent lattice dynamics in MoS{sub x}Se{sub (2–x)} alloys
- Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China)
- Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8969 (Japan)
- Department of Electronic Engineering, Ming Chi University of Technology, Taishan, Taipei 243, Taiwan (China)
- Department of Electrical Engineering, National Taiwan Ocean University, Keelung 202, Taiwan (China)
We report on room temperature, polarization-resolved Raman scattering measurements on layered crystals of the series MoS{sub x}Se{sub (2–x)} (0 ≤ x ≤ 2) grown by chemical vapor transport technique. The results reveal two distinct sets of features related to the E{sub 2g}{sup 1} and A{sub 1g} modes of pure members of series. As composition x changes, the in-plane E{sub 2g}{sup 1} mode shows two-mode behavior, whereas the out-of-plane A{sub 1g} mode presents more complex evolution. The MoSe{sub 2}-like branch reveals the splitting associated with the altering arrangement of S and Se atoms around Mo and the resulting changes in the dipole moment of the molecule. The X-ray diffraction measurements confirm that the samples are single-phase materials of 2H-type structure over the entire range of the sulfide composition x, while the scanning transmission electron microscopy imaging reveals a random arrangement of the S and Se atoms. Modified random-element-isodisplacement model is adopted to predict the behavior of the individual modes in the alloys. The model successfully confirms the two-mode behavior exhibited by the MoS{sub x}Se{sub (2–x)} series.
- OSTI ID:
- 22402654
- Journal Information:
- Journal of Applied Physics, Vol. 116, Issue 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
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