Twisted plasma waves driven by twisted ponderomotive force

Figure  1.  Structure of the ponderomotive potential $\Phi_\text{pond}$ (in a. u.) of one LG laser pulse (a) and two beating LG laser pulses (b) in transverse plane ($ y $-$ z $). The ponderomotive force ${\boldsymbol F}_\text{pond} = - \nabla \Phi_\text{pond}$ has an azimuthal component only for two beating waves.

Figure  2.  3D PIC simulation results of electric field and fluid velocity distribution at transverse plane ($ y $-$ z $ plane) at the centre of simulation box ($ x $ = 15 μm) and the time 320 fs after the laser has passed by. (a), (b), and (c) show transverse slices of $ E_x $, $ E_{\theta} $, and $ E_r $.

Figure  3.  PIC results of transverse profile of (a) electron density perturbation $\delta n_{\rm{e}}$, (c) axial magnetic field $ B_x $ and (e) azimuthal magnetic field $ B_{\theta} $ at the centre of simulation box ($ x $ = 15 μm) and the time 320 fs after the laser has passed by. The dashed lines shown in the transverse slices are the line outs used to plot the graphics on the right. The plots on the right, (b), (d), and (f), are line outs from the slices plotted against the position along the line outs $ d $ plotted in (a), (c), and (e). $ d $ is the coordinate along the dashed lines. Solid lines in (b), (d) and (f) are theory predictions, for the same situation considered in Table 1.

Figure  4.  PIC results of transverse profile of (a) electron density perturbation $ \delta n_e $, (b) axial magnetic field $ B_x $ and (c) azimuthal magnetic field $ B_{\theta} $ at the centre of simulation box ($ x $ = 15 μm) and the time 320 fs after the laser has passed by.