We report on anomalous field enhancement of terahertz transmission in metallic, rectangular coaxial geometries. The integration of a particle in the hole not only results in a factor of eight increase in normalized transmittance compared to that of the hole-only counterpart, but it also tailors polarization-dependent transmission discrepancy encountered in arrays of rectangular holes. Our experimental and numerical studies on the impact of geometrical dimensions of the integrated particles indicate that dipolar localized surface plasmons of the particles contribute substantially to the terahertz field enhancement through coupling with surface plasmons and localized surface plasmons of the holes.
© 2010 Optical Society of America
Optics at Surfaces
Original Manuscript: August 26, 2009
Revised Manuscript: February 13, 2010
Manuscript Accepted: February 19, 2010
Published: March 17, 2010
Xinchao Lu, Jiaguang Han, and Weili Zhang, "Transmission field enhancement of terahertz pulses in plasmonic, rectangular coaxial geometries," Opt. Lett. 35, 904-906 (2010)