Polarization dependence photoluminescence in flexible two-dimensional MoS₂ for lattice deformation characterization

Since Nobel Physics Prize in 2010 about graphene, intense research endeavors have been paid worldwide to comprehend the intrinsic characteristics of two-dimensional (2D) materials and explore their cutting-edge applications in bioengineering, energy storage and conversion, and nanoelectronics. 2D heterostructures consisting of various 2D materials are receiving extensive interests nowadays. However, there is a lattice deformation when different 2D materials are stacked together. Characterization of each 2D layer’s lattice deformation facilitates with the optimized 2D device design. In this project, we study the rotation angle dependent photoluminescence (PL) of one atomic layer of 2D MoS₂ under a serious of external mechanical deformations. The PL shows a dependence with the sample rotation angle at stretched status. The intensities of two PL peaks (627 nm and 679 nm) have strong angle dependence and a serious of mechanical deformations (up to 10%) are performed. This research result can be used to accurately identify the value of lattice deformation in 2D heterostructures.

Reference:
[1]Ling, Xi, et al. "Low-frequency interlayer breathing modes in few-layer black phosphorus." Nano letters 15.6 (2015): 4080-4088.