Axion-like-particle generation by laser-plasma interaction.

Axion, a hypothetical particle that is crucial to quantum chromodynamics and dark matter theory, has not yet been found in any experiment. With the improvement of laser technique, a much stronger quasi-static electromagnetic field can be created in laboratory via laser-plasma interaction. In this article, we discuss the feasibility of axion's exploring experiment using planar and cylindrically symmetric laser-plasma field as background while probing with an ultrafast superstrong laser or an x-ray free-electron laser with high photon number. Compared to classical magnet design, the axion source in laser-plasma interaction trades the accumulating length for the source's interacting strength. Besides, a structured field in the plasma creates a tunable transverse profile of the interaction and improves the signal-noise ratio via the mechanisms such as phase-matching. We give some simple layouts and estimate detectable parameters like axion production and probe's polarization rotation, which reveals the possibility of future laser-plasma axion source in laboratory.