Biaxial versus uniaxial strain tuning of single-layer MoS2

• 作者: Felix Carrascoso Riccardo Frisenda Andres Castellanos-Gomez
• 来源期刊: 纳米材料科学（英文版）
• 年，卷（期）: 2022,（1）
• 页码范围: 44-51
• 页数: 8页
• 语种: 中文

摘要

Strain engineering has arisen as a powerful technique to tune the electronic and optical properties of two-dimensional semiconductors like molybdenum disulfide(MoS2).Although several theoretical works predicted that biaxial strain would be more effective than uniaxial strain to tune the band structure of MoS2,a direct experimental verification is still missing in the literature.Here we implemented a simple experimental setup that allows to apply biaxial strain through the bending of a cruciform polymer substrate.We used the setup to study the effect of biaxial strain on the differential reflectance spectra of 12 single-layer MoS2 flakes finding a redshift of the excitonic features at a rate between-40 meV/％and-110 meV/％of biaxial tension.We also directly compare the effect of biaxial and uniaxial strain on the same single-layer MoS2 finding that the biaxial strain gauge factor is 2.3 times larger than the uniaxial strain one.