Detection of QED vacuum nonlinearities in Maxwell's equations by the use of waveguides

We present a novel method for detecting nonlinearities, due to quantum electrodynamics through photon-photon scattering, in Maxwell's equation. The photon-photon scattering gives rise to self-interaction terms, which are similar to the nonlinearities due to the polarisation in nonlinear optics. These self-interaction terms vanish in the limit of parallel propagating waves, but if instead of parallel propagating waves the modes generated in wavesguides are used, there will be a non-zero total effect. Based on this idea, we calculate the nonlinear excitation of new modes and estimate the strength of this effect. Furthermore, we suggest a principal experimental setup.