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New effects in quantum vacuum: photon undulator and transition radiation

We consider a new optical property of quantum vacuum, as predicted by quantum electrodynamics. It is associated with the propagation of an intense laser pulse, in the presence of a periodic static magnetic field. The existence of an effective charge distribution for the intense laser beam is demonstrated. The photon undulator effect results from the spacetime modulations of this effective charge. This is similar to an electron undulator, where the electron beam is replaced by a photon beam. We also discuss a closely related effect, which can be called photon transition radiation in vacuum. It is associated with the effective charge variation at a magnetic boundary. This work could lead to new experimental configurations for quantum vacuum research with future multi-Peta–Watt laser systems.