Fig. 1. Schematic of metal PPWG structure

Fig. 2. Normalized tangential electric field distribution of TE₁ mode in metal PPWG. (a)(d) Normalized mode field distribution obtained by simulation; (b)(e) electric field distribution in air and metal; (c)(f) electric field distribution in metal

Fig. 3. Comparison of approximate expressions and simulation results. (a) Real part of n_eff changes with a/λ₀; (b) imaginary part of n_eff changes with a/λ₀; (c) real part of n_eff changes with frequency; (d) imaginary part of n_eff changes with frequency

Fig. 4. Relative error of approximate expression. (a) Relative error changes with frequency; (b) relative error changes with a/λ₀

Fig. 5. Variation of group velocity dispersion and real part of effective refractive index with frequency and partial enlarged view of TE₁ mode