Laser-Driven Fusion Energy with Picosecond Pulses for Block Ignition

doi:10.1117/3.2073374.ch10

Book: Laser Plasma Physics: Forces and the Nonlinearity Principle

Author(s): Heinrich Hora

Published: 2016

https://doi.org/10.1117/3.2073374.ch10

Author Affiliations +

Abstract

Laser and plasma physics with forces and the nonlinearity principle to be applied to controlled nuclear fusion energy generation was considered in Chapters 8 and 9. While Chapter 9 presented some aspects of the presently very broad stream of experiments and theory using traditional lasers with pulses in the nanosecond range, this is interwoven with the crucially new physics of very short and nonthermal acceleration of plasma blocks to which Chapter 8 introduced the achievements of the past 15 to 20 years. The push for developing the picosecond interaction indeed came from the developments of laser-driven fusion thanks to the progress made with the chirped pulse amplification (CPA) (see Chapter 8.1) offering subpicosecond laser pulses above PW power. For the broad stream of laser fusion with nanosecond pulses to heat and compress fusion fuel to more than 1000 times the solid state densities for controlled ignition of exothermal reactions, it was significant that densities of 2000 times the solid state were achieved (Azechi et al. 1991). This compression and the generation of highest-gain DT fusion neutrons was possible only thanks to the smoothing of the laser beams using the random phase plates discovered by Kato et al. (1984). This smoothing (Hora 2006) will enable in one immediate step to work with the secondharmonics in the NIF project at LLNL in Livermore, CA instead of the usually applied third harmonics (Hora 2006) to increase the irradiated laser pulse energy from 2 to 6 MJ (Roth 2014).