Symmetry-Dependent Exciton-Phonon Coupling in 2D and Bulk MoS2 Observed by Resonance Raman Scattering
Symmetry-Dependent Exciton-Phonon Coupling in 2D and Bulk MoS2 Observed by Resonance Raman Scattering
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DOI：
10.1103/physrevlett.114.136403
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发表时间：
2015-04-02
影响因子：
8.6
通讯作者：
Pimenta, Marcos A.
中科院分区：
文献类型：
--
作者：
Carvalho, Bruno R.;Malard, Leandro M.;Pimenta, Marcos A.
这项工作描述了对一层、两层和三层（1L、2L、3L）和大块二硫化钼样品进行的共振拉曼研究，使用30多种不同的激光激发线覆盖可见光范围，并关注二硫化钼拉曼散射光谱的两个最显著特征的强度(E-2g（1)和a （1g）波段）。实验得到了这些波段的拉曼激发谱图，发现当激发激光与MoS2的A、B激子共振时，A（1g）特征增强，而当激发激光接近2.7 eV时，E-2g(1)特征增强。我们从激子-声子相互作用的对称性分析中表明，负责E-2g(1)共振的模式被确定为最近预测的高能C激子。
This work describes a resonance Raman study performed on samples with one, two, and three layers (1L, 2L, 3L), and bulk MoS2, using more than 30 different laser excitation lines covering the visible range, and focusing on the intensity of the two most pronounced features of the Raman scattering spectrum of MoS2 (E-2g(1) and A(1g) bands). The Raman excitation profiles of these bands were obtained experimentally, and it is found that the A(1g) feature is enhanced when the excitation laser is in resonance with A and B excitons of MoS2, while the E-2g(1) feature is shown to be enhanced when the excitation laser is close to 2.7 eV. We show from the symmetry analysis of the exciton-phonon interaction that the mode responsible for the E-2g(1) resonance is identified as the high energy C exciton recently predicted.