Manipulation and generation of the spatially ultra-compact and high quality THz beam.

The generation of a spatially ultra-compact and high quality terahertz (THz) beam has been a challenging issue at present for advancing the THz technology. Here, we demonstrate an efficient scheme from the laser-plasma interaction in a spatially modulated magnetized plasma to control the THz beam. An analytical THz radiation field and the two-dimensional particle-in-cell simulations based on the scheme are carried out. The spatial distribution, the intensity, and the polarization of the THz beam are highly modulated and controlled by the laser field, external magnetic field, and self-generated plasma channel. A spatially modulated ultra-compact and high-brightness THz beam with the multiple THz field distribution patterns is generated. This scheme opens a practical and economical path to develop the THz technology in various fields. [ABSTRACT FROM AUTHOR]