We demonstrate tunable, enhanced 0th-order transmission through a metal–dielectric nanohole array device with a subwavelength-thick liquid crystal (LC) layer. The LC filled the nanoholes and formed a subwavelength covering layer, which is then capped by a top cover layer. The wavelength where the transmittance dip associated with the LC occurs is determined by the anisotropic refractive-index component of the LC, which is normal to the surface of the hole array. A low-refractive-index cover layer suppresses unwanted higher-order diffraction, which results in an enhancement of the 0th-order transmission, which is closely related to laterally propagating surface plasmon polaritons. The proposed design is expected to help realize tunable plasmonic devices with high optical transmittance.
© 2014 Optical Society of America
Original Manuscript: November 6, 2013
Revised Manuscript: January 13, 2014
Manuscript Accepted: January 15, 2014
Published: February 25, 2014
Takayuki Matsui, Hiroyuki Yoshida, Atsushi Miura, Junji Kobashi, Naoki Ikeda, Yoshimasa Sugimoto, and Masanori Ozaki, "Tunable enhanced 0th-order transmission in a metal–dielectric hole array covered with a subwavelength liquid crystal layer," Opt. Lett. 39, 1262-1265 (2014)