Induced Local EMP and Secondary THz Radiation in Sensor Window Materials from Intense Femtosecond Pulses at Long Range

"Time Domain Corporation (TDC) proposes to provide the military with a detailed physical understanding of EMP generation in air induced by intense femtosecond laser pulses under self-focusing conditions. Theoretical models developed will include the fullspatio-temporal dynamics of laser pulse-plasma interaction. The physical mechanism that lead to the charge separation and the subsequent EMP generation will be described in detail and its dependence on the initial laser pulse conditions will beinvestigated. Other, methods to generate intense THz radiation via nonlinear frequency mixing in air and materials will be studied. Particularly, the propagation of two laser pulses under self-focusing and plasma generation will be studied. Animportant part of our effort will concentrate on the design of detection techniques and design of experiments using high peak power femtosecond laser pulses in air. All of the required instrumentation will be identified as well as experimental setup forperforming the measurements. Detection techniques for the measurement of the absolute radiometric intensity of the EMP radiation, its temporal profile, polarization and emission patterns will be addressed. In this proposal, TDC presents an approach,based on sound scientific research principles, that will lead to a prototype femtosecond laser system using focused geometry on a laboratoryscale to induce and measure plasma generated EMP. The result will b