Abstract

The evolution of the optical phonons in layered semiconductor alloys SnSe(1–x)Sx is studied as a function of the composition by using polarized Raman spectroscopy with six different excitation wavelengths (784.8, 632.8, 532, 514.5, 488, and 441.6 nm). The polarization dependences of the phonon modes are compared with transmission electron diffraction measurements to determine the crystallographic orientation of the samples. Some of the Raman modes show significant variation in their polarization behavior depending on the excitation wavelengths. It is established that the maximum intensity direction of the Ag2 mode of SnSe(1−x)Sx (0 ≤ x ≤ 1) does not depend on the excitation wavelength and corresponds to the armchair direction. It is additionally found that the lower-frequency Raman modes of Ag1, Ag2 and B3g1 in the alloys show the typical one-mode behavior of optical phonons, whereas the higher-frequency modes of B3g2, Ag3 and Ag4 show two-mode behavior.

Details

Title
Optical phonons of SnSe(1−x)Sx layered semiconductor alloys
Author
Tharith, Sriv 1 ; Nguyen Thi Minh Hai 2 ; Lee, Yangjin 3 ; Lim, Soo Yeon 4 ; Nguyen Van Quang 2 ; Kim Kwanpyo 3 ; Cho Sunglae 2 ; Cheong Hyeonsik 4 

 Sogang University, Department of Physics, Seoul, Korea (GRID:grid.263736.5) (ISNI:0000 0001 0286 5954); Royal University of Phnom Penh, Department of Physics, Phnom Penh, Cambodia (GRID:grid.20440.32) (ISNI:0000 0001 1364 8832) 
 University of Ulsan, Department of Physics and Energy Harvest Storage Research Center (EHSRC), Ulsan, Korea (GRID:grid.267370.7) (ISNI:0000 0004 0533 4667) 
 Yonsei University, Department of Physics, Seoul, Korea (GRID:grid.15444.30) (ISNI:0000 0004 0470 5454); Institute for Basic Science (IBS), Center for Nanomedicine, Seoul, Korea (GRID:grid.410720.0) (ISNI:0000 0004 1784 4496) 
 Sogang University, Department of Physics, Seoul, Korea (GRID:grid.263736.5) (ISNI:0000 0001 0286 5954) 
Publication year
2020
Publication date
2020
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2424342064
Copyright
© The Author(s) 2020. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.