Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
Nano Lett. 2013 Mar 13;13(3):1029-33. doi: 10.1021/nl304213s. Epub 2013 Feb 15.
We present a novel method for sensitive mapping of optical intensity distributions at subdiffraction-limited resolution. This is achieved with a novel device, a plasmonic nanopore, which combines a plasmonic bowtie nanoantenna with a 10 nm-in-diameter solid-state nanopore. Variations in the local optical intensity modulate the plasmonic heating, which we measure electrically through changes in the ionic conductance of the nanopore. We demonstrate the method by profiling the focal volume of a 10 mW laser beam that is tightly focused by a high-numerical-aperture microscope objective. The results show a complex three-dimensional intensity distribution that closely matches predictions obtained by theoretical calculations of the optical system. In addition to laser profiling, the ionic conductance of a nanopore is also shown to provide quantitative estimates of the temperature in the proximity of single plasmonic nanostructures.
我们提出了一种新的方法，能够在亚衍射极限分辨率下灵敏地绘制光强分布。这是通过一种新的装置，即等离子体纳米孔来实现的，它将等离子体蝶形纳米天线与 10nm 直径的固态纳米孔结合在一起。局部光强的变化会调制等离子体加热，我们通过纳米孔的离子电导的变化来进行电测量。我们通过对由高数值孔径显微镜物镜紧密聚焦的 10mW 激光束的焦体积进行剖析来验证该方法。结果显示了一个复杂的三维强度分布，与光学系统的理论计算预测非常吻合。除了激光剖析之外，纳米孔的离子电导还可以对单个等离子体纳米结构附近的温度进行定量估计。
