During the laser wakefield acceleration, electron beams are strongly focused by the plasma fields and reach extremely high brightness thanks to their femtosecond durations and micrometric sizes. In the synchrotron radiation sources, relativistic electrons oscillate generating X-rays and the brightness and duration of the particle beam is transferred to the radiation. This makes laser-plasma accelerators very attractive for development of novel ultracompact X-ray sources, where wiggling field can be produced either by the plasma itself, or by a counter-propagating laser beam, or by a conventional permanent magnet undulator. Being recently demonstrated, these sources are capable of combining femtosecond durations together with collimation and spatial coherence, and they offer remarkable perspectives for numerous applications.
Artwork demonstrating the principle of the nanowire plasma undulator for X-rays generation