Ultrahigh acceleration of plasma by picosecond terawatt laser pulses for fast ignition of fusion

• Published in: Laser and particle beams Vol. 30; no. 2; pp. 233 - 242
• Main Authors: Lalousis, P., Földes, I.B., Hora, H.
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 01.06.2012
• Subjects: Deuterium; Doppler effect; Electron clouds; Flame propagation; Fluid dynamics; Fluid flow; Fluid mechanics; Hydrodynamics; Ignition; Inertia; Lasers; Particle beams; Plasma; Plasma acceleration; Plasma physics; Space charge; Temperature effects; Tritium; Uncompressed fusion fuel; Laser driven fusion energy; Fast ignition; Fusion flame; Nonlinear (ponderomotive) force acceleration; Side-on ignition
• ISSN: 0263-0346; 1469-803X
• DOI: 10.1017/S0263034611000875

A fundamental different mechanism dominates laser interaction with picosecond-terawatt pulses in contrast to the thermal-pressure processes with ns pulses. At ps-interaction, the thermal effects are mostly diminished and the nonlinear (ponderomotive) forces convert laser energy instantly with nearly 100% efficiency into the space charge neutral electron cloud, whose motion is determined by the inertia of the attached ion cloud. These facts were realized only by steps in the past and are expressed by the ultrahigh plasma acceleration, which is more than few thousand times higher than observed by any thermokinetic mechanism. The subsequent application for side-on ignition of uncompressed fusion fuel by the ultrahigh accelerated plasma blocks is studied for the first time by using the genuine two-fluid hydrodynamics. Details of the shock-like flame propagation can be evaluated for the transition to ignition conditions at velocities near 2000 km/s for solid deuterium-tritium.