Electron deflection driven by terahertz pulses from laser-plasma interactions

Traditional electron accelerators usually use the radio-frequency field as the driving field. In contrast, the terahertz radiation, with a shorter wavelength and a higher accelerating gradient, has the capability to work as the driver of compact electron accelerators in the future. In addition, the terahertz pulse can also provide an ultrafast modulated field to compress and measure the electron pulse width. Recently, the interactions between terahertz filed and electrons have attracted increasing attention. Intense laser-solid interactions can produce both a high-energy terahertz pulse and a high-charge electron beam simultaneously. This advantage enables a unique platform for the terahertz control of electrons and the terahertz pump-electron probe experiments. Here, by taking a feasible experimental layout as an example, we first investigate the interactions of a terahertz pulse with a co-propagating electron beam. Systematic discussions on the influences of several parameters on the terahertz field-induced electron deflection are presented via numerical simulations. We find that a strong terahertz electric field or the long pulse duration will enhance the deflection. Furthermore, the deflection depends strongly on the terahertz waveform. A preliminary experiment is performed to qualitatively demonstrate the relevant analysis.