Título: Photon Acceleration and Related Topics

Orador: José Tito Mendonça (GoLP/IPFN, Instituto Superior Técnico, Universidade de Lisboa)

Abstract:

The concept of photon acceleration was introduced in physics more than thirty years ago. In principle, it could lead to coherent and unlimited up-shift of a photon beam frequency, from the infrared to the XUV. Laser experiments, using ionisation fronts and wakefields, have shown that this process could produce significant frequency up- shifts in the visible, with nearly 100 efficiencies. They have also shown clear evidence of photon trapping and pulse compression.

In recent years, interest has been given to superluminal fronts, produced by a flying focus, as well to electron beam wakes. According to the existing models, frequency upshifts of more than 10 times the initial frequency could be attained, with considerable power amplification. This would lead to tuneable and powerful radiation sources in a near future. In this talk we review the main theoretical models, including ray-tracing, full-wave and wave-kinetics, and describe old and new experimental configurations.