Demonstrating Fuel Magnetization and Laser Heating Tools for Low-cost Fusion Energy

Magnetized liner inertial fusion (MagLIF) [1] is an inertial confinement fusion (ICF) scheme using cylindrical compression of magnetized, preheated deuterium-tritium (DT) gas. A 10 – 30 T axial magnetic field reduces electron thermal conductivity allowing near-adiabatic compression at implosion velocities of order 100 km/s, much lower than the 300 km/s or more required for conventional ICF. Preheating to at least 100 eV ensures that keV temperatures are reached with a convergence ratio no greater than 30. The compressed magnetic field confines alpha particles in the radial direction, replacing the ρR > 0.3 g/cm2 requirement of conventional ICF, which requires high convergence ratios, with a BR > 0.6 T m requirement [2]. The ignition temperature of low ρR, magnetized DT is about 7 keV, slightly higher than the 4.5 keV required at high ρR. The confinement time is provided by the inertia of the target, as in conventional ICF. MagLIF experiments on Z [3] typically use a 5.58 mm outer diameter, 0.465 mm thick, 7.5 mm long Beryllium liner filled with high pressure deuterium gas in a 10 T axial magnetic field, imploded at a velocity of 70 km/s using a 16 MA, 100 ns rise-time current pulse. The gas is typically preheated using the Z beamlet laser (ZBL), delivering 1-2.5 kJ in 2.5 ns at a wavelength of 0.53 μm.