Nanoscale investigation of light-matter interactions mediated by magnetic and electric coupling
Nanoscale investigation of light-matter interactions mediated by magnetic and electric coupling
复制标题
磁电耦合介导的光与物质相互作用的纳米级研究
DOI：
10.3990/1.9789036528764
复制
发表时间：
2009
期刊：
影响因子：
3.6
通讯作者：
M. Burresi
中科院分区：
文献类型：
--
作者：
M. Burresi
在纳米光学中，光被控制在小于波长的长度尺度上。因此，光子纳米结构的研究需要超过衍射极限的分辨率。近场显微镜由于能够提供亚波长分辨率，自20世纪80年代以来一直是纳米光学的支柱之一。本论文对近场显微镜核心的涂层探针的电磁响应进行了深入的研究。由此产生的见解，我们成功地进行了一种新型的纳米级调查，涉及在纳米级的磁场和电场。
首先，我们证明了孔径探针可以同时映射光子纳米结构中光的两个面内电场分量。通过对这两个组件进行相敏近场测量，我们重建了光子晶体波导中光的高度结构化的面内偏振态，从而观察到纳米级的偏振奇异性。
其次，我们发现涂层探针对光频磁场的面外分量敏感。虽然这种磁耦合不会导致磁场的直接检测，但它会在探针和样品之间产生一种新的相互作用。通过控制探针位置接近光子晶体纳米腔中捕获的光的快速变化的磁场分量的最大值，我们诱导了共振频率的新的蓝移。此外，我们能够通过磁相互作用增加腔的光子寿命。
第三，通过设计纳米尺度的孔径探针的几何形状，我们成功地明确映射了光子结构中传播光的磁场。通过使用超材料的概念，我们同时可视化光的电和磁分量与亚波长分辨率和相位灵敏度。
In nano-optics, light is controlled at length scales smaller than the wavelength. Consequently, investigations of photonic nanostructures require a resolution beyond the diffraction limit. Near-field microscopy has been one of the pillars of nano-optics since 1980s, as it can provide the necessary subwavelength resolution. This thesis provides a careful study of the electro-magnetic response of the coated probe which forms the heart of a near-field microscope. With the resulting insights we succeed in performing a new type of nanoscale investigation which involves both magnetic and electric fields at the nanoscale.
Firstly, we show that an aperture probe can simultaneously map the two in-plane electric field components of light in a photonic nanostructure. By performing phase-sensitive near-field measurements of both components, we reconstruct the highly structured in-plane polarization state of light in a photonic crystal waveguide, leading to the observation of polarization singularities at the nanoscale.
Secondly, we found that a coated probe is sensitive to the out-of-plane component of a magnetic field at optical frequency. Although this magnetic coupling does not lead to a direct detection of the magnetic field, it gives rise to new a type of interaction between probe and sample. By controlling the probe position near a maximum of a rapidly varying magnetic field component of light trapped in a photonic crystal nanocavity, we induce a novel blue-shift of the resonance frequency. In addition, we are able to increase the photon lifetime of the cavity through magnetic interaction.
Thirdly, by engineering the geometry of an aperture probe at the nanoscale, we succeed in unambiguously mapping the magnetic field of propagating light in a photonic structure. By using metamaterials concepts, we simultaneously visualize the electric and magnetic component of light with subwavelength resolution and phase sensitivity.