Fig. 3: Spatiotemporal evolution of the spherical wavefront of the Coulomb field.
From: Ultrafast visualization of an electric field under the Lorentz transformation
a–d, Experimentally obtained spatiotemporal transverse electric-field profiles (Ex) for propagation distances (D) of 5 (a), 15 (b), 25 (c) and 209 mm (d) after the wavefront has passed through Al foil. In this set-up, we rotate the ZnTe by 90° around the beam axis, so the transverse direction is x, as shown in Supplementary Fig. 7. e–h, Simulated spatiotemporal electric-field profiles (Ex) for D of 5 (e), 15 (f), 25 (g) and 209 mm (h) after the wavefront has passed through a metallic boundary. The peak positions of the electric-field strength in z′ at each x in the experimental results are plotted as black circles. The error bars reflect the timing jitter (r.m.s.) between the electron beam and the probe laser (Supplementary Section 3). The green dashed curve shows the theoretically estimated peak positions: \({z^{\prime}} = {- {\sqrt {{x^2} + {D^2}}} + {2D}}\).
