[OPTICAL REVIEW Vol. 18, No. 4 (2011) 311-316]
© 2011 The Japan Society of Applied Physics

Characteristics of Coupled Plasmon Modes in Asymmetric Layered System

Michael FLOCKERT*, Masanobu HARAGUCHI, and Toshihiro OKAMOTO

Department of Optical Science and Technology, The University of Tokushima, Tokushima 770-8506, Japan

(Received September 29, 2010; Accepted May 24, 2011)

We used an asymmetric layered system functioning as a plasmon waveguide coupler to couple surface plasmon modes with gap plasmon modes. The planar system was analyzed by the transfer matrix method to design the optical dimensions of the system. We simulated the effective mode indexes and H-field distribution of the coupled modes, for different gap widths and refractive indexes. For the calculated modes the propagation lengths were calculated. Furthermore, a sample structure was fabricated and odd gap plasmon modes were excited with a coupling prism in an attenuated-total-reflection (ATR) configuration. The mode index measurement showed good agreement with the simulation data.

Key words: surface plasmon, gap plasmon, waveguide, ATR, transfer-matrix

*E-mail address: flockert_michael@gmx.de