Strain Relaxation of Monolayer WS₂ on Plastic Substrate

详细信息    查看全文

• 作者：Qianhui Zhang ; Zhenyue Chang ; Guanzhong Xu ; Ziyu Wang ; Yupeng Zhang ; Zai-Quan Xu ; Shujian Chen ; Qiaoliang Bao ; Jefferson Zhe Liu ; Yui-Wing Mai ; Wenhui Duan ; Michael S. Fuhrer and Changxi Zheng
• 刊名：Advanced Functional Materials
• 出版年：2016
• 出版时间：December 20, 2016
• 年：2016
• 卷：26
• 期：47
• 页码：8707-8714
• 全文大小：2479K
• ISSN：1616-3028

文摘

Strain-dependent electrical and optical properties of atomically thin transition metal dichalcogenides may be useful in sensing applications. However, the question of how strain relaxes in atomically thin materials remains not well understood. Herein, the strain relaxation of triangular WS₂ deposited on polydimethylsiloxane substrate is investigated. The photoluminescence of trions (X^–) and excitons (X⁰) undergoes linear redshifts of ≈20 meV when the substrate tensile strain increases from 0 to 0.16. However, when the substrate strain further increases from 0.16 to 0.32, the redshifts cease due to strain relaxation in WS₂. The strain relaxation occurs through formation of wrinkles in the WS₂ crystal. The pattern of wrinkles is found to be dependent on the relative angle between an edge of the triangular WS₂ crystal and tensile strain direction. Finite element simulations of the strain distribution inside the WS₂ crystals explain the experimental observations.