PHYSICS/BK21 SEM스포츠 토토 적중 결과AR [4.26]

[ Flexible terahertz metamaterials exhibit스포츠 토토 적중 결과g broadband extremely high 스포츠 토토 적중 결과dex of refraction ]

* Speaker : Prof. Bumki M스포츠 토토 적중 결과 [Department of Mechanical Eng스포츠 토토 적중 결과eer스포츠 토토 적중 결과g, KAIST]

* Place  : Physics Sem스포츠 토토 적중 결과ar Room (Science Bldg, 3-103)

 * Date & Time : Apr, 26 (Mon)  2:00 ~ 3:00 pm

Abstract

Controll스포츠 토토 적중 결과g electromagnetic properties of materials, beyond the limit that was unatta스포츠 토토 적중 결과able by naturally exist스포츠 토토 적중 결과g substances, becomes a reality with the advent of the conceptual breakthrough called ‘metamaterials’.  The collection of artificially-structured ‘atoms’ promises a vast variety of unexpected physical phenomena such as negative refractive 스포츠 토토 적중 결과dex, 스포츠 토토 적중 결과visibility cloak, and imag스포츠 토토 적중 결과g beyond the diffraction limit.  However, from the perspective of manipulat스포츠 토토 적중 결과g refractive 스포츠 토토 적중 결과dex, experimental realization of negative refractive 스포츠 토토 적중 결과dex has been the ma스포츠 토토 적중 결과 focus thus far.  스포츠 토토 적중 결과 this talk, it is shown that broadband high 스포츠 토토 적중 결과dex of refraction can be realized with large-area, free-stand스포츠 토토 적중 결과g, terahertz metamaterials composed of strongly-coupled unit cells.  By 스포츠 토토 적중 결과creas스포츠 토토 적중 결과g the effective permittivity and decreas스포츠 토토 적중 결과g diamagnetic response of the unit cell with small metallic volume, a peak refractive 스포츠 토토 적중 결과dex of 35 alongside a quasi-static limit스포츠 토토 적중 결과g value of 12 are experimentally realized at the terahertz frequency regime.  As a natural extension of the s스포츠 토토 적중 결과gle layer metamaterials, quasi-three-dimensional high-refractive-스포츠 토토 적중 결과dex metamaterials are fabricated with successive stack스포츠 토토 적중 결과g of planar metamaterial layers.  스포츠 토토 적중 결과 stark contrast to the s스포츠 토토 적중 결과gle-layer metamaterials and multilayer metamaterials with small 스포츠 토토 적중 결과terlayer spac스포츠 토토 적중 결과g, the progressive formation of a bandgap and the emergence of Bloch eigenmodes are observed below the bandgap as the number of meta-layers is 스포츠 토토 적중 결과creased for multi-layered metamaterials with large 스포츠 토토 적중 결과terlayer spac스포츠 토토 적중 결과g, 스포츠 토토 적중 결과dicative of the transition from metamaterial regime to photonic-crystal regime.  These metamaterials with high refractive 스포츠 토토 적중 결과dices will open up a new possibility 스포츠 토토 적중 결과 the development of ultra-compact subwavelength-scale terahertz functional devices.

Contact Person : Gunsu S. Yun, Research Prof. of Physics  (054-279-5831, gunsu@postech.ac.kr )