  The propagation of a probe electromagnetic field through a counterpropagating
strong plane wave is investigated. The effects of the electromagnetic
field-(pseudo)scalar axion field interaction and of the self-interaction of the
electromagnetic field mediated by virtual electron-positron pairs in the
effective Lagrangian approach are included. First, we show that if the strong
field is circularly polarized, contrary to the leading-order nonlinear QED
effects, the axion-photon interaction induces a chiral-like birefringence and a
dichroism in the vacuum. The latter effect is explained by evoking the
conservation of the total angular momentum along the common propagation
direction of probe and the strong wave, which allows for real axion production
only for probe and strong fields with the same helicity. Moreover, in the case
of ultra-short strong pulses, it is shown that the absorption coefficients of
probe photons depend on the form of the pulse and, in particular, on the
carrier-envelope phase of the strong beam. The present results can be exploited
experimentally to isolate nonlinear vacuum effects stemming from light-axion
interaction, especially at upcoming ultra-strong laser facilities, where
stringent constraints on the axion-photon coupling constant are in principle
provided.
