Polarized Raman Study of 2-dimensional Layered Gallium Selenide
- 주제(키워드) Raman spectroscopy , Gallium Selenide , 라만분광학 , 갈륨셀레나이드
- 발행기관 서강대학교 일반대학원
- 지도교수 정현식
- 발행년도 2017
- 학위수여년월 2017. 2
- 학위명 석사
- 학과 및 전공 일반대학원 물리학과
- 실제URI http://www.dcollection.net/handler/sogang/000000061403
- 본문언어 영어
- 저작권 서강대학교 논문은 저작권보호를 받습니다.
초록/요약
Gallium Selenide (GaSe) is a layered semiconductor composed of post-transition metal Gallium (Ga) and chalcogen Selenidum (Se). It can be used in a photodevice thanks to high photoresponsivity and external quantum efficiency. [1,2] We investigated layered GaSe by polarized Raman spectroscopy from monolayer to bulk. The A1g1 mode blueshifts with increasing thickness while other peaks do not change much. We also observed low frequency shear modes coming from inter-layer vibrations in the range of 5-25 cm-1. The layer number of GaSe was determined by the position of the shear modes and atomic force microscopy. We also found domains with different stacking orders even in same-thickness flakes. We measured 3-layer GaSe samples in particular. We found several types of low-frequency spectra that correspond to different stacking orders.
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