Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Nano Lett. 2011 Dec 14;11(12):5159-64. doi: 10.1021/nl2023405. Epub 2011 Nov 28.
We have developed an efficient chemical exfoliation approach for the high-throughput synthesis of solution-processable, high-quality graphene sheets that are noncovalently functionalized by alkylamine. Purely coherent nonlinear optical response of these graphene sheets has been investigated, using near-infrared, visible, and ultraviolet continous wave and ultrafast laser beams. Spatial self-phase modulation has been unambiguously observed in the solution dispersions. Our results suggest that this coherent light scattering is due to a broadband, ultrafast, and remarkably huge third-order optical nonlinearity χ(3), which is a manifestation of the graphene's cone-shaped large-energy-scale band structure. Our experimental findings endow graphene new potentials in nonlinear optical applications.
我们开发了一种高效的化学剥离方法，用于高通量合成可溶液加工的高质量石墨烯片，这些石墨烯片通过烷基胺非共价功能化。使用近红外、可见和紫外连续波和超快激光束研究了这些石墨烯片的纯相干非线性光学响应。在溶液分散体中清楚地观察到空间自相位调制。我们的结果表明，这种相干光散射是由于宽带、超快和非常大的三阶光学非线性 χ(3)，这是石墨烯锥形大能量尺度能带结构的表现。我们的实验结果赋予了石墨烯在非线性光学应用中的新潜力。
