Nonlinear Double-Layer Bragg Waveguide: Analytical and Numerical Approaches to Investigate Waveguiding Problem

Figure 9

Case 2(c). The inner radius 𝑅₁=2. Marked eigenvalues: linear eigenvalue 𝛾≈2.619 (red dot 𝛾²≈6.859) and nonlinear eigenvalues 𝛾≈2.701, 𝛾≈3.131, and 𝛾≈3.779 (green, blue, and black dots, resp., 𝛾²≈7.295, 𝛾²≈9.803, and 𝛾²≈14.281).