Properties of defected one-dimensional terahertz plasmonic crystal films in a metal air-gap waveguide

Abstract

We investigated properties of localized modes of one-dimensional terahertz plasmonic crystal films with defects in a metal air-gap waveguide by terahertz time-domain spectroscopy experiments and finite-difference time-domain simulations. A defect was created by varying the width of an air slit at the center of the plasmonic crystal film. The donor (accept)-like defect modes were observed when the width of the defect air slit increases (decreases) from an initial width. The quality factor increases abruptly as the air-gap size decreases, while the defect mode frequency slightly decreases. The high quality-defect mode was examined for terahertz sensor applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.3658255]