Spatial and temporal evolution of electromagnetic pulses generated at Shenguang-II series laser facilities

The distribution and sources of EMPs produced at Shenguang-II (SG-II) series laser facilities are systematically investigated. The results indicate that the EMP amplitudes in the SG-II ps PW laser are very strong, one order higher than those from the SG-II laser facility. EMPs outside the target chamber decrease exponentially with the distance from the measuring points to the target chamber center at the two laser facilities. Moreover, EMPs can be remarkably reduced when the picosecond laser together with the nanosecond laser is incident to targets compared to the SG-II ps PW laser alone. The resulting conclusions are expected to offer experimental supports for further effective EMPs shielding design and achievement in high-power laser facilities.