  We report the first high-repetition rate generation and simultaneous
characterization of nanosecond-scale return currents of kA-magnitude issued by
the polarization of a target irradiated with a PW-class high-repetition-rate
Ti:Sa laser system at relativistic intensities. We present experimental results
obtained with the VEGA-3 laser at intensities from 5e18 - 1.3e20 W/cm2. A
non-invasive inductive return-current monitor is adopted to measure the
derivative of return-currents on the order of kA/ns and analysis methodology is
developed to derive return-currents. We compare the current for copper,
aluminium and Kapton targets at different laser energies. The data shows the
stable production of current peaks and clear prospects for the tailoring of the
pulse shape, promising for future applications in high energy density science,
e.g. electromagnetic interference stress tests, high-voltage pulse response
measurements, and charged particle beam lensing. We compare the target
discharge of the order of hundreds of nC with theoretical predictions and a
good agreement is found.
