Elastic Wave Scattering: Mie-like Resonances

A plane wave scatters off a circular obstacle. The scattered field is expanded in partial waves: ψ_scat = Σ_n a_n H_n(kr) e^{inθ}. Resonances occur when ka ≈ mode zeros.

ka = 3.0 (size param)
Impedance ratio Z 2.0
Wave speed c₀ 1.0
Color shows total wave amplitude (incident + scattered). The cylinder is the dark circle. Mie resonances produce dramatic near-field enhancements and complex far-field patterns.