Production of Net Fusion Energy from Laser-Heated Target Plasmas

Abstract
The heating of a small particle of deuterium‐tritium by laser radiation is considered and conditions for energy gain determined. The size of the D‐T particle for a balance of energy input and neutron energy output is computed as a function of initial plasma temperature. The electrical energy required for this breakeven condition is shown and increases as the inverse fourth power of laser efficiency. Because electrons are first heated by the laser radiation and then must transfer their energy to ions by collisions, a computation of electron‐ion thermalization is presented. These results show that electron‐ion thermalization through collisions applies a severe limitation on most cases for producing net fusion energy and must be considered in a consistent manner for smaller particles.