Intra-cycle depolarization of ultraintense laser pulses focused by off-axis parabolic mirrors

Abstract

A study of the structure of the electric and magnetic fields of ultraintense laser pulses focused by an off-axis parabolic mirror is reported. At first, a theoretical model is laid out, whose final equations integration allows the space and time structure of the fields to be retrieved. The model is then employed to investigate the field patterns at different times within the optical cycle, for off-axis parabola parameters normally employed in the context of ultraintense laser-plasma interaction experiments. The results show that nontrivial, complex electromagnetic field patterns are observed at the time at which the electric and magnetic fields are supposed to vanish. The importance of this effect is then studied for different laser polarizations, f numbers and off-axis angles.

EuPRAXIA – a compact, cost-efficient particle and radiation source

“…For this reason, laserdriven (laser wakefield acceleration, LWFA), electron beam-driven (plasma wakefield acceleration, PWFA) as well as hybrid (combining LWFA and PWFA) acceleration approaches are under consideration [13]; concurrently, both external (with the electron beam generated outside of the plasma accelerator) [14][15][16] and internal (with the electron beam generated inside the plasma accelerator) injection methods are also investigated [17][18][19]. Beyond the plasma acceleration stage itself, the EuPRAXIA study additionally focuses on researching high power laser systems (in 040012-3 particular pump sources at high average power and repetition rate, diagnostics, laser alignment) [20][21][22], ultrashort electron beam dynamics [10,23] and transport [24][25][26][27], single-shot electron diagnostics [28], synchronization and machine control [29], FEL and secondary source design [30] as well as other aspects. Figure 1 outlines the main elements generally planned for the EuPRAXIA beamline layout starting from the high-power laser system and RF injector to be used for generating the driver, and driver or witness beam, respectively, depending on the final design.…”