Strain-modulated excitonic gaps in mono- and bi-layer MoSe<sub>2</sub>

Strain-modulated excitonic gaps in mono- and bi-layer MoSe₂

Ji Jianting, Zhang Anmin, Xia Tianlong, Gao Po, Jie Yinghao, Zhang Qian, Zhang Qingming^†,

(a) Optical image of monolayer and bilayer MoSe₂. (b) Raman phonon in the monolayer case. (c) Home-made setup for applying strain on films. (d) Schematic of quantitatively estimated strain. The arc length of bended PET substrate is L and its thickness is d. If the straight-line distance between any two points on the PET substrate is taken as x, one can calculate the radius of curvature R. Tuning R by changing x gives variable strains e. For accuracy, the two points should be as close as possible to the arc top.