An Approximate Formula of the Effective Refractive Index of the Metal-Insulator-Metal Surface Plasmon Polariton Waveguide in the Infrared Region

作者：Park Junghyun^*; Lee Byoungho

来源：Japanese Journal of Applied Physics, 2008, 47(11): 8449-8451.

DOI：10.1143/JJAP.47.8449

• surface plasmon
• plasmonic waveguide
• effective refractive index
• Drude model

We present an approximate formula for the effective refractive index of the symmetric plasmonic mode of the metal-insulator-metal waveguide in the infrared region. It is shown that, in the long-wavelength region, the effective refractive index asymptotes to a wavelength-independent constant value. The proposed formula that gives this constant value is in good agreement with that obtained by solving the rigorous transcendental characteristic equation. We believe that this formula can be used to analyze and design lots of plasmonic-waveguide-based devices. [DOI: 10.1143/JJAP.47.8449]

• 出版日期2008-11