2019年第80回応用物理学会秋季学術講演会

講演情報

一般セッション(口頭講演)

3 光・フォトニクス » 3.9 テラヘルツ全般

[20p-E206-1~11] 3.9 テラヘルツ全般

2019年9月20日(金) 13:45 〜 16:45 E206 (E206)

松原 英一(旭川高専)、鈴木 左文(東工大)

16:30 〜 16:45

[20p-E206-11] Development of terahertz artificial materials based on the composites of metal-dielectric woven wires

〇(M2)Siqi Zhao1、Ya-Lei Chang2、Dejun Liu1、Ryuji Iwasa1、Bowen You1、Ja-Yu Lu2、Toshiaki Hattori1 (1.Univ.Tsukuba、2.Cheng Kung Univ.)

キーワード:Terahertz, artificial materials, metal-dielectric woven wires

Photonic structures found in biology have diverse periodic structures and make animals, insects and plants sensitive to the light with colorful and bright appearances. The fundamental theory shows the photonic bandgap is the intrinsic property of a periodic structure to reflect light waves, which is specified by the pitch size, layer thicknesses and dielectric constants. The reflection or transmission ability of an artificial material can thus be engineered to increase the efficiency of the designed optical devices, such as the reflectors, waveguides, and sensors.
In tradition, semiconductors are the terahertz (THz) artificial materials because plasmonic frequency in THz band can be modified via the intrinsic carrier concentrations. The semiconductor-slab-stacking structures are therefore workable for the THz Bragg reflectors when the critical dielectrics can be designed for each semiconductor slab. However, such artificial materials based on semiconductors are expensive to prepare, not flexible, and have high reflection loss at the input interface due to the high THz refractive indices.
Meta-surface (i.e., metamaterial) based on a periodic metal pattern is another type of THz artificial material when local surface resonance can be realized among the unit pattern cells. However, to fabrication the subwavelength scale metal patterns, the rigid substrate is required in the photolithography, physical/chemical etching and the metal coating processes. Although the meta-surfaces on the polymer substrates have high flexibility, the deformable range and shape are still not acceptable in the applications, such as the waveguides, or absorbers with various shapes or volumes. To efficiently manipulate THz photons/wave at the near-field and remote locations, the cheap, soft and substrate-free artificial materials are urgently requested.