Polarized Nonlinear Nanoscopy of Metal Nanostructures

详细信息    查看全文

• 作者：Naveen Kumar Balla ; Carolina Rendón-Barraza ; Luong Mai Hoang ; Pawel Karpinski ; Esteban Bermúdez-UreñaSophie Brasselet
• 刊名：ACS Photonics
• 出版年：2017
• 出版时间：February 15, 2017
• 年：2017
• 卷：4
• 期：2
• 页码：292-301
• 全文大小：821K
• ISSN：2330-4022

文摘

Nonlinear signals from metal nanostructures are known to be highly polarization-dependent, due to the intrinsic vectorial nature of nonlinear optical coupling. Nonlinear optical polarization responses contain important information on the near-field properties of nanostructures; however, they remain complex to monitor and to model at the nanoscale. Polarization resolved nonlinear optical microscopy can potentially address this question; however, the recorded signals are generally averaged over the diffraction-limited size of a few hundreds of nanometers, thus, missing the spatial specificity of the nanostructure’s optical response. Here we present a form of polarization resolved microscopy, named polarization nonlinear nanoscopy, which reveals subdiffraction scale vectorial variations of electromagnetic fields, even though the intensity image is diffraction-limited. We show that by exploiting, at a single subdiffraction pixel level, the information gained by the polarization-induced modulation, it is possible to spatially map the vectorial nature of plasmonic nonlinear optical interactions in nanostructures, revealing in particular surface contributions, retardation effects, and anisotropic spatial confinements.