09:30 〜 11:30
▼ [20a-PA3-10] Identification of stacking configurations in a few-layered-MoS2 sample by low-frequency Raman spectroscopy
キーワード:2D materials, MoS2, Raman spectroscopy
Two-dimensional (2D) layered materials, such as MoS2, are often used in electronic and optoelectronic devices as active media in the form of a few layers. The orientations of different layers and their stacking configurations alter the crystal symmetry, thereby modifying the band structure and the electronic properties of the device. Since MoS2 has layer stacking, and layer number dependent properties, a thorough understanding of the stacking sequences and the number of layers is essential for a full exploration of their potential. Interlayer Raman modes, such as, shear and breathing modes that arise due to the in-plane and the out-of-plane vibrations of entire layers can characterize stacking configurations and determine the number of layers. Since these modes originate from the weak interlayer van der Waals interactions, they appear in the ultra-low-frequency range in the Raman spectrum. This research focuses on identifying different stacking configurations of MoS2 layers using ultra-low-frequency Raman spectroscopy.