hBN覆盖与封装少层石墨烯中纳米尺度不均匀性的超分辨成像
Super-resolution imaging of nanoscale inhomogeneities in hBN-covered and encapsulated few-layer graphene
AI总结：
本文利用hBN双曲声子极化激元与石墨烯等离激元耦合的超透镜效应，实现了hBN覆盖三层及封装四层石墨烯中亚衍射尺寸不均匀性的超分辨放大成像，并证实极化激元色散具有堆叠依赖性。
摘要：
将少层石墨烯（FLG）封装在六方氮化硼（hBN）中会在FLG中引起纳米尺度的不均匀性，包括堆叠畴的变化和形貌缺陷。由于衍射极限的限制，表征这些不均匀性具有挑战性。最近，利用声子极化激元（PhP）辅助的近场成像已经展示了封装四层石墨烯（4LG）中堆叠畴的可视化。然而，其背后的耦合机制以及对亚衍射尺寸不均匀性进行成像的能力仍然未知。在此，我们借助超透镜效应，获得了hBN覆盖三层石墨烯（TLG）和封装4LG中亚衍射尺寸不均匀性的直接复制图像和放大图像。该超透镜效应由hBN的双曲PhP与FLG的等离激元极化激元耦合所介导。利用近场显微镜，我们通过确定hBN覆盖TLG中极化激元色散具有堆叠依赖性来识别这种耦合。我们的工作展示了不均匀性的超分辨和放大成像，为实现均匀封装的FLG输运样品以研究关联物理铺平了道路。
英文摘要：
Encapsulating few-layer graphene (FLG) in hexagonal boron nitride (hBN) can cause nanoscale inhomogeneities in the FLG, including changes in stacking domains and topographic defects. Due to the diffraction limit, characterizing these inhomogeneities is challenging. Recently, the visualization of stacking domains in encapsulated four-layer graphene (4LG) has been demonstrated with phonon polariton (PhP)-assisted near-field imaging. However, the underlying coupling mechanism and ability to image subdiffractional-sized inhomogeneities remain unknown. Here, we retrieve direct replicas and magnified images of subdiffractional-sized inhomogeneities in hBN-covered trilayer graphene (TLG) and encapsulated 4LG, enabled by the hyperlensing effect. This hyperlensing effect is mediated by hBN's hyperbolic PhP that couple to the FLG's plasmon polaritons. Using near-field microscopy, we identify the coupling by determining the polariton dispersion in hBN-covered TLG to be stacking-dependent. Our work demonstrates super-resolution and magnified imaging of inhomogeneities, paving the way for the realization of homogeneous encapsulated FLG transport samples to study correlated physics.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
