论文标题
单层MOS $ _2 $的双轴和单轴应变调谐
Biaxial versus uniaxial strain tuning of single-layer MoS$_2$
论文作者
论文摘要
应变工程已成为一种强大的技术，可以调整二维半导体（如钼）（MOS2）等二维半导体的电子和光学性质。尽管几项理论作品预测双轴菌株比单轴菌株更有效，以调整MOS2的带状结构，但文献中仍缺少直接的实验验证。在这里，我们实施了一个简单的实验设置，该设置允许通过弯曲十字形聚合物底物施加双轴应变。我们使用该设置来研究双轴菌株对12个单层MOS2薄片的差分反射光谱的影响，以-40 meV/％和-110 MeV/％的双轴张力找到了激子特征的红移。我们还直接比较了双轴和单轴应变对同一单层MOS2的影响，发现双轴应变量表因子是单轴应变一倍的2.3倍。
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.
