Determination of the macroscopic permeability of swiss rolls

In this paper the properties of an ensemble of Swiss rolls are investigated. By fitting an analytical solution to the results of the simulation, the macroscopic permeability and permittivity are determined. For the simulations, boundary integral equations are used, discretized by the method of moments (MoM), which leads to a set of linear equations. To reduce the CPU-time needed to solve the set of equations, a low-frequency stable multilevel fast multipole algorithm (MLFMA) is invoked. The obtained macroscopic material parameters show that Swiss rolls are a magnetic metamaterial.