Figure A2.

Light field enhancement by a HEA microparticle (on glass) at different wavelengths calculated by FDTD for spherical (a) and snowman (b) structures as observed in experiments (Figure 3b; incident E-field is $\left|E\right|=1$. HEA is modeled as homogeneous refractive index $(n+i\kappa )$ of HEA (Figure 2b). Boundary conditions: perfect matching layer.