Polarization dependence of double resonant Raman scattering band in bilayer graphene |
| |
| Affiliation: | 1. Department of Physics, Sogang University, Seoul 121-742, Republic of Korea;2. School of Computational Sciences, Korean Institute for Advanced Study, Seoul 130-722, Republic of Korea;1. Universidade Federal da Paraíba, Departamento de Física, CCEN, Caixa Postal 5008, 58051-970, João Pessoa, PB, Brazil;2. Universidade Federal de Campina Grande, Departamento de Física, CCT, Caixa Postal 10071, 58109-970, Campina Grande, PB, Brazil;1. Universidade Federal Rural de Pernambuco, Departamento de Física, 52171-900, Recife, PE, Brazil;2. Institute of Nanotechnology, Karlsruhe Institute of Technology, D-76021, Karlsruhe, Germany;1. Department of Mechanical Engineering, Iowa State University, Ames, IA, 50011, United States;2. School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, Shandong, 266033, PR China;3. College of Mechatronics Engineering, Guangdong Polytechnic Normal University, Guangzhou, 510635, PR China;1. School of Power and Mechanical Engineering, Wuhan University, Wuhan, Hubei 430072, China;2. Department of Mechanical Engineering, Iowa State University, Ames, IA 50010, USA |
| |
| Abstract: | The polarization dependence of the double resonant Raman scattering (2D) band in bilayer graphene (BLG) is studied as a function of the excitation laser energy. It has been known that the complex shape of the 2D band of BLG can be decomposed into four Lorentzian peaks with different Raman frequency shifts attributable to four individual scattering paths in the energy–momentum space. From our polarization dependence study, however, we reveal that each of the four different peaks is actually doubly degenerate in its scattering channels, i.e., two different scattering paths with similar Raman frequency shifts for each peak. We find theoretically that one of these two paths, ignored for a long time, has a small contribution to their scattering intensities but are critical in understanding their polarization dependences. Because of this, the maximum-to-minimum intensity ratios of the four peaks show a strong dependence on the excitation energy, unlike the case of single-layer graphene (SLG). Our findings thus reveal another interesting aspect of electron–phonon interactions in graphitic systems. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
