Figure 4
From: High-Energy, Short-Duration Bursts of Coherent Terahertz Radiation from an Embedded Plasma Dipole
Radiation frequency, frad vs. plasma density, n0, of the plasma strip. The frequency of the radiation is determined at 100 μm from the centre of the dipole. The error bars indicate the full width at half-maximum of the spectrum. The solid line is the plasma frequency as a function of the plasma density, i.e.\({f}_{p}={(2\pi )}^{-1}\sqrt{{e}^{2}{n}_{0}/(m{\varepsilon }_{0})}\). In the figure legend, the pulse duration, τ, is given in femtoseconds. The wavelength of the second pulse, λ2, and its spot size, σ, are given in micrometers. The wavelength of the first laser pulse is fixed at 0.8 μm.
