Fig. 1. Scheme for generating nearly single-cycle laser pulses. The incident pulse irradiates a thin foil, producing an ultra-short transmitted pulse and a reflected pulse. Electrostatic fields (green dashed line) and (green dotted line) are produced at both sides of the surface (at ) of the CEL (red solid line) at the initial stage of the interaction. Ions (blue solid line) remain at rest. The distribution of the electrons corresponds to the case where the CEL just reaches the back side of the target. The CEL then oscillates and disperses, as shown in Figures 2c and 2d.

Fig. 2. 1D PIC simulation results for ( and ), , and . (a) Electron and proton trajectories and their density peaks versus time. (b) Laser profile (blue solid line) and charge density of electrons (black solid line) and ions (red solid line) at for the case of moving ions. (c) Electron and proton trajectories and (d) laser profile (blue solid line) and charge density of electrons (black solid line) and ions (red solid line) at for the case of ions at rest.

Fig. 3. (a) Amplitude peak (black square) and duration (blue triangle) of transmitted pulses versus foil thickness . For the incident laser, ( and ). The foil density is . Laser profile (blue solid line) and charge density of electrons (black solid line) and ions (red solid line) for ( and ) and (b) , (c) .

Fig. 4. Laser profile (blue solid line) and charge density of electrons (black solid line) and ions (red solid line) for ( and ). The foil density is , and the foil thickness is .

Fig. 5. Electron (red circle) and ion (blue circle) distribution and the laser profiles in the (, ) plane for foils with and irradiated by CP laser pulses with ( and ) at . The axial laser profiles at are denoted by the black solid lines.