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Title: Composition dependent lattice dynamics in MoS{sub x}Se{sub (2–x)} alloys

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.
Authors:
 [1] ;  [2] ;  [3] ;  [4] ; ;  [1] ; ;  [5] ;  [6] ;  [7]
  1. Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China)
  2. (Poland)
  3. Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
  4. (China)
  5. National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8969 (Japan)
  6. Department of Electronic Engineering, Ming Chi University of Technology, Taishan, Taipei 243, Taiwan (China)
  7. Department of Electrical Engineering, National Taiwan Ocean University, Keelung 202, Taiwan (China)
Publication Date:
OSTI Identifier:
22402654
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALLOYS; ATOMS; DIPOLE MOMENTS; LAYERS; MOLYBDENUM SELENIDES; POLARIZATION; RAMAN EFFECT; SILICON OXIDES; TEMPERATURE RANGE 0273-0400 K; TRANSMISSION ELECTRON MICROSCOPY; VAPORS; X-RAY DIFFRACTION