Subwavelength Plasmonic Waveguides and Plasmonic Materials

Table 2

The lengths of evanescent tails at different wavelengths for metal-insulator boundary.

Wavelength (𝜆)	0.5 μm	1.55 μm	10.5 μm	300 μm
Frequency (𝑐0/𝜆)	600 THz	193 THz	28 THz	1 THz
𝜀Al	−36.5 + 𝑗9.4	−252 + 𝑗46	−8e3 + 𝑗5.2e3	−6e4 + 𝑗9e4
𝜀Air	1.0	1.0	1.0	1.0
Decay factor (𝛾/𝑘0)	0.1678	0.0631	0.0112	0.0041
Tail length (𝛿)	0.23 μm	1.95 μm	74.7 μm	5800 μm
Relative tail length (𝛿/𝜆)	0.47	1.26	7.12	19.49