F. Consoli, R. De Angelis, L. Duvillaret, P. L. Andreoli, M. Cipriani, G. Cristofari, G. Di Giorgio, F. Ingenito & C. Verona
We describe the first electro-optical absolute measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy.
The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.
Interactions between high energy and high intensity lasers with matter produce particle flux and electromagnetic radiation over a wide range of energy. The generation of transient fields of very high intensity in the radiofrequency-microwave regime has been observed for femtosecond to nanosecond laser pulses with 10¹¹–10²º W/cm² intensity, on both conductive and dielectric targets. These fields have a bandwidth of several GHz and last for hundreds of nanoseconds. They often cause saturation and damage to the electronic equipment inside and near the experimental chamber, but on the other hand can also become an effective diagnostic tool …
Scientific Reports | 6:27889 | DOI: 10.1038/srep27889