Spatiotemporal evolution of high-power relativistic laser pulses in electron-positron-ion plasmas

The spatiotemporal pulse dynamics of a high-power relativistic laser pulse interacting with an electron-positron-ion plasmas is investigated theoretically and numerically. The occurrence of pulse compression is studied. The dependence of the mechanism on the concentration of the background ions in electron positron plasma is emphasized.

Figure 1

(Color online) Normalized intensity $\left({\mathbf{A}}^{\mathbf{2}}\right)$ plots as a function of time. The side-bar shows the variation in normalized intensity. The region near to center ($\rho =0,\tau =0$) shows maximum intensity (corresponding to the top of bar) while as we move away from the central ($\rho =0,\tau =0$) region, the intensity decreases (corresponding to the middle and lower part of the bar respectively).

Figure 2

(Color online) The dependence of normalized intensity $\left({\mathbf{A}}^{\mathbf{2}}\right)$ plots (upper row) and potential $\left(\varphi \right)$ plots (lower row) as a function of the ion-to-electron density ratio $\left(\alpha \right)$. The side-bar shows the variation in normalized intensity (in upper row) and potential (in lower row). The region near to center ($\rho =0,\tau =0$) shows maximum intensity/potential (corresponding to the top of bar) while as we move away from the central ($\rho =0,\tau =0$) region, the intensity/potential decreases (corresponding to the middle and lower part of the bar respectively).

Figure 3

(Color online) Normalized axial amplitude as a function of propagation distance.

Figure 4

(Color online) Pulse width parameter $\left(g\right)$ as a function of $\alpha$.