D' Archangel Jeffrey, Tucker Eric, Kinzel Ed, Muller Eric A, Bechtel Hans A, Martin Michael C, Raschke Markus B, Boreman Glenn
CREOL, The College of Optics & Photonics, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL 32816, USA.
Opt Express. 2013 Jul 15;21(14):17150-60. doi: 10.1364/OE.21.017150.
Optical metamaterials have unique properties which result from geometric confinement of the optical conductivity. We developed a series of infrared metasurfaces based on an array of metallic square loop antennas. The far-field absorption spectrum can be designed with resonances across the infrared by scaling the geometric dimensions. We measure the amplitude and phase of the resonant mode as standing wave patterns within the square loops using scattering-scanning near-field optical microscopy (s-SNOM). Further, using a broad-band synchrotron-based FTIR microscope and s-SNOM at the Advanced Light Source, we are able to correlate far-field spectra to near-field modes of the metasurface as the resonance is tuned between samples. The results highlight the importance of multi-modal imaging for the design and characterization of optical metamaterials.
光学超材料具有独特的性质，这些性质源于光导率的几何限制。我们基于一系列金属方环天线开发了一系列红外超表面。通过缩放几何尺寸，可以设计出在红外波段具有共振的远场吸收光谱。我们使用散射扫描近场光学显微镜（s-SNOM）测量方环内作为驻波模式的共振模式的幅度和相位。此外，利用基于宽带同步加速器的傅里叶变换红外显微镜和先进光源处的s-SNOM，当在样品之间调节共振时，我们能够将远场光谱与超表面的近场模式相关联。结果突出了多模态成像在光学超材料设计和表征中的重要性。
