Elibol Kenan, Bayer Bernhard C, Hummel Stefan, Kotakoski Jani, Argentero Giacomo, Meyer Jannik C
Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria.
Sci Rep. 2016 Jun 27;6:28485. doi: 10.1038/srep28485.
We demonstrate the use of combined simultaneous atomic force microscopy (AFM) and laterally resolved Raman spectroscopy to study the strain distribution around highly localised deformations in suspended two-dimensional materials. Using the AFM tip as a nanoindentation probe, we induce localised strain in suspended few-layer graphene, which we adopt as a two-dimensional membrane model system. Concurrently, we visualise the strain distribution under and around the AFM tip in situ using hyperspectral Raman mapping via the strain-dependent frequency shifts of the few-layer graphene's G and 2D Raman bands. Thereby we show how the contact of the nm-sized scanning probe tip results in a two-dimensional strain field with μm dimensions in the suspended membrane. Our combined AFM/Raman approach thus adds to the critically required instrumental toolbox towards nanoscale strain engineering of two-dimensional materials.
我们展示了结合使用同步原子力显微镜（AFM）和横向分辨拉曼光谱来研究悬浮二维材料中高度局部变形周围的应变分布。使用AFM探针作为纳米压痕探针，我们在悬浮的少层石墨烯中诱导局部应变，少层石墨烯被用作二维膜模型系统。同时，我们通过少层石墨烯的G和2D拉曼带的应变相关频率偏移，利用高光谱拉曼映射原位可视化AFM探针下方和周围的应变分布。由此我们展示了纳米尺寸扫描探针尖端的接触如何在悬浮膜中产生微米尺寸的二维应变场。我们的AFM/拉曼联合方法因此为二维材料的纳米级应变工程所需的关键仪器工具箱增添了内容。
