论文标题
中性和带电的激子相互作用，在不均匀应变工程WS $ _2 $中
Neutral and charged excitons interplay in non-uniformly strain-engineered WS$_2$
论文作者
论文摘要
我们研究了受控非均匀应变场的二维半导体中激子的响应。在我们进行非均匀应变工程的方法中，WS $ _2 $单层被悬挂在三角形孔上。大型（$> 2 \; \％$），非常均匀（$> 0.28 \; \％/μm$），并且通过用惰性气加压来诱导单层诱导单层诱导的原位可调节应变。我们观察到峰值移动和光谱形状变化，WS $ _2 $的光致发光光谱。我们将这些变化解释为提高自由电子密度的标志，并导致中性激子转化为高应变区域中的Trions。我们的结果将非均匀的应变工程建立为一种新颖且有用的实验“旋钮”，用于调整2D半导体的光电特性。
We investigate the response of excitons in two-dimensional semiconductors subjected to controlled non-uniform strain fields. In our approach to non-uniform strain-engineering, a WS$_2$ monolayer is suspended over a triangular hole. Large ($>2\;\%$), strongly non-uniform ($>0.28\;\%/μm$), and in-situ tunable strain is induced in the monolayer by pressurizing it with inert gas. We observe peak shifts and spectral shape changes in the photoluminescence spectra of strained WS$_2$. We interpret these changes as a signature of increased free electron density and resulting conversion of neutral excitons to trions in the region of high strain. Our result establishes non-uniform strain engineering as a novel and useful experimental `knob' for tuning optoelectronic properties of 2D semiconductors.
