title: Self-induced uniaxial strain in MoS2 monolayers with local van der Waals-stacked interlayer interactions.
abstract: Strain engineering is an effective method to tune the properties of electrons and phonons in semiconductor materials, including two-dimensional (2D) layered materials (e.g., MoS2 or graphene). External artificial stress (ExAS) or heterostructure stacking is generally required to induce strains for modulating semiconductor bandgaps and optoelectronic functions. For layered materials, the van der Waals-stacked interlayer interaction (vdW-SI) has been considered to dominate the interlayer stacking and intralayer bonding. Here, we demonstrate self-induced uniaxial strain in the MoS2 monolayer without the assistance of ExAS or heterostructure stacking processes. The uniaxial strain occurring in local monolayer regions is manifested by the Raman split of the in-plane vibration modes E2g(1) and is essentially caused by local vdW-SI within the single layer MoS2 due to a unique symmetric bilayer stacking. The local stacked configuration and the self-induced uniaxial strain may provide improved understanding of the fundamental interlayer interactions and alternative routes for strain engineering of layered structures.
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.|‡State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.|∥Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Kenan
authors.initials: K
authors.lastname: Zhang
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Shuhong
authors.initials: S
authors.lastname: Hu
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Tianning
authors.initials: T
authors.lastname: Zhang
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Xiaohao
authors.initials: X
authors.lastname: Zhou
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Tian-Xin
authors.initials: TX
authors.lastname: Li
authors.affiliation: §Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 639798, Singapore.
authors.forename: Hong Jin
authors.initials: HJ
authors.lastname: Fan
authors.affiliation: ‡State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
authors.forename: Guozhen
authors.initials: G
authors.lastname: Shen
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: †National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.|∥Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|⊥Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou 213164, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Dai
keywords: MoS2; Raman; first-principles plane-wave calculations; self-induced; uniaxial strain; van der Waals stacking