Space and time resolved measurement of surface magnetic field in high intensity short pulse laser matter interactions

Magnetic fields produced by the interaction of intense laser beams on the surface of flat solid targets have been characterized. Laser probe polarimetry diagnosed the spatial and temporal evolution of the magnetic field by measuring the changes in the probe beam polarization due to Cotton-Mouton and Faraday effects at different times with respect to a pump laser pulse. The results show that 1 ps after the interaction of the pump laser with the target, a magnetic field of the order of a few MG is already present over a region ≈150 μm in diameter centered around the interaction spot. From the spatial and temporal evolutions of the magnetic field, we infer information on the resistivity of the material, showing evidence of a strongly magnetized resistivity.Magnetic fields produced by the interaction of intense laser beams on the surface of flat solid targets have been characterized. Laser probe polarimetry diagnosed the spatial and temporal evolution of the magnetic field by measuring the changes in the probe beam polarization due to Cotton-Mouton and Faraday effects at different times with respect to a pump laser pulse. The results show that 1 ps after the interaction of the pump laser with the target, a magnetic field of the order of a few MG is already present over a region ≈150 μm in diameter centered around the interaction spot. From the spatial and temporal evolutions of the magnetic field, we infer information on the resistivity of the material, showing evidence of a strongly magnetized resistivity.