  A coupled system of volume integral and hydrodynamic equations is solved to
analyze electromagnetic scattering from nanostructures consisting of metallic
and dielectric parts. In the metallic part, the hydrodynamic equation relates
the free electron polarization current to the electric flux and effectively
"updates" the constitutive relation to enable the modeling of nonlocality. In
the metallic and the dielectric parts, the volume integral equation relates the
electric flux and the free electron polarization current to the scattered
electric field. Unknown electric flux and free electron polarization current
are expanded using Schaubert-Wilton-Glisson basis functions. Inserting these
expansions into the coupled system of the volume integral and hydrodynamic
equations and using Galerkin testing yield a matrix system in unknown expansion
coefficients. An efficient two-level iterative solver is proposed to solve this
matrix system. This approach "inverts" the discretized hydrodynamic equation
for the coefficients of the free electron polarization current and substitutes
the result in the discretized volume integral equation. Outer iterations solve
this reduced matrix system while the inner iterations invert the discretized
hydrodynamic equation at every iteration of the outer iterations. Numerical
experiments are carried out to demonstrate the accuracy, the efficiency, and
the applicability of the proposed method.
