Figure 2
From: High-Energy, Short-Duration Bursts of Coherent Terahertz Radiation from an Embedded Plasma Dipole
Displacement and release of trapped electrons from a 2D PIC simulation with normalized peak laser amplitudes a0 = 0.6 (where a0 = eE0/(mcω0), ω0 = 2πc/λ0 and the normalizing wavelength λ0 = 1 μm), respective wavelengths λ1 = 0.8 μm, λ2 = 0.76 μm, duration τ = 30 fs for both laser pulses, and unperturbed plasma density n0 = 4.97 × 1018 cm−3. (a). The dipole field in 2D, (b). the perturbation of the electron density δn/n0 (blue), and the electric field (red) along the axis. (c) The electric field probed at three different positions inside the dipole in the axial direction (at y = 200 μm). (d–f). The phase portraits of the electrons close to the collision centre of the pulses, at t = 0.75, 0.8, and 0.83 ps, respectively.
