[7p-A409-1~5] 4.7 Terahertz Photonics

▼ [7p-A409-3] Near-field Measurements of Terahertz Meta-atoms with Localized Terahertz Sources

〇Kazunori Serita¹, Juraj Darmo², Iwao Kawayama¹, Hironaru Murakami¹, Masayoshi Tonouchi¹ (1.Osaka Univ., 2.Vienna Univ. Tech.)

Keywords:terahertz, meta-atom, nonlinear optical crystal

We present the direct measurements of terahertz meta-atoms, an elementary unit of metamaterials, by using locally generated terahertz waves in the near-field region. In contrast to a conventional far-field terahertz spectroscopy or imaging, our technique features the localized emission of coherent terahertz pulses on a sub-wavelength scale, which has a potential for visualizing details of dynamics of each meta-atom. The obtained data show the near-field coupling among the meta-atoms and the impact of the electric field distribution from the excited meta-atom to neighbor meta-atoms. The observable LC resonance response is enhanced with an increase of numbers of meta-atoms. Furthermore, our approach also has a potential for visualizing the individual mode of meta-atom at different terahertz irradiation spots. These data can help us to understand the important role of the meta-atom in metamaterials and develop the novel terahertz components and devices such as active terahertz metamaterial and compact, high-sensitive bio-sensor devices.