Terawatt Pulsed THz Sources from Picosecond Laser-Solid Interactions*

Terawatt scale THz opens new avenues for study into extreme light-matter interactions at the low end of the frequency spectrum and with effectively single-cycle pulses[1]. There has been steady progress for many years on increasing THz pulse power and energy via solid, liquid and gaseous targets, with an eventual goal of >1 TW peak powers. This talk presents the result of years of study into foil, wire, and microchannel targets irradiated with the joule-class Multi-Terawatt laser and kilojoule-class OMEGA EP laser. The experiments were observed to generate THz sources in the range of 10’s of millijoules to greater than 1 joule of pulse energy[2], which correspond to a terawatts in peak power. The physics of THz generation from each target type is examined analytically and compared to the experimental results. Future uses of these powerful THz sources are discussed, with an emphasis on extreme light–matter interactions using powerful THz sources to drive matter into new states as well as a probe fusion relevant plasmas.

1) Guoqian Liao, Yutong Li; Perspectives on ultraintense laser-driven terahertz radiation from plasmas. Phys. Plasmas 1 September 2023; 30 (9): 090602.

2) G. Bruhaug, H. G. Rinderknecht, K. Weichman, M. VanDusen-Gross, J. P. Palastro, M. S. Wei, S. P. Regan, Y. E, K. Garriga, X.-C. Zhang, G. W. Collins, and J. R. Rygg, "Joule-class THz pulses from microchannel targets," Opt. Lett. 49, 1737-1740 (2024)