MATHICSE-GroupAbdulle, AssyrHuber, Martin ErnstLemaire, Simon2019-10-152019-10-152019-10-152016-08-0110.5075/epfl-MATHICSE-271330https://infoscience.epfl.ch/handle/20.500.14299/162025A new optimization-based numerical method is proposed for the solution of diffusion problems with sign-changing conductivity coefficients. In contrast to existing approaches, our method does not rely on the discretization of a stabilized equation and the convergence of the scheme can be proved without any symmetry assumption on the mesh near the interface where the conductivity sign changes.text::working paper