Multi-trace, Single Source

This contribution introduces an integral equation based domain decomposition method for the modelling of scattering of time harmonic electromagnetic waves by a penetrable obstacle. It is a single source method constructed from the gap idea that lies at the heart of the global multi-trace formulation. The advantages compared to the existing global multi-trace formulations are that it only requires half of the unknowns, and that the system matrix is well-conditioned without requiring further regularisation or preconditioning.