2020/12/31 by Felix Carrascoso, Riccardo Frisenda, Andres Castellanos-Gomez · 1 citation
Physics and Astronomy · #physics.app-ph #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1016/j.nanoms.2021.03.001
5 figures + 1 table in the main text. 6 figures in the supp. info
arxiv created 2021/05/07 · arxiv updated 2021/05/11
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.