论文标题
通过化学蒸气沉积生长的MOS2层中的层间激子
Controlling interlayer excitons in MoS2 layers grown by chemical vapor deposition
论文作者
论文摘要
组合MOS $ _2 $单层形成多层，可以访问新功能。在这项工作中，我们检查了MOS $ _2 $同质式样品在化学蒸气沉积（CVD）中生长的堆叠顺序与价状态的层层偶联与人工堆叠的CVD单层双层。我们表明，与3R双层相比，在2H堆叠中允许双层上的孔离域化，并导致较大的A-B激子分离，并导致较大的A-B激子分离，在较大的A-B激子分离中，孔和电子都局限于各个层。比较2H和3R的反射率光谱允许提取约$ t_ \ perp = 49 $ MEV的层间耦合能。使用层间激子的吸收和A-B激子分离，以将大面积的范德华结构与CVD材料组装在一起的大面积范德华结构，获得了非常相似的结果，可以将大面积的范德华结构与CVD材料组装在一起。除了包括激激效应在内的DFT计算以外，还证实了与我们的实验一致的有效层间耦合的签名。
Combining MoS$_2$ monolayers to form multilayers allows to access new functionalities. In this work, we examine the correlation between the stacking order and the interlayer coupling of valence states in MoS$_2$ homobilayer samples grown by chemical vapor deposition (CVD) and artificially stacked bilayers from CVD monolayers. We show that hole delocalization over the bilayer is allowed in 2H stacking and results in strong interlayer exciton absorption and also in a larger A-B exciton separation as compared to 3R bilayers, where both holes and electrons are confined to the individual layers. Comparing 2H and 3R reflectivity spectra allows to extract an interlayer coupling energy of about $t_\perp=49$ meV. Obtaining very similar results for as-grown and artificially stacked bilayers is promising for assembling large area van der Waals structures with CVD material, using interlayer exciton absorption and A-B exciton separation as indicators for interlayer coupling. Beyond DFT calculations including excitonic effects confirm signatures of efficient interlayer coupling for 2H stacking in agreement with our experiments.
