Physics / mechanism
Inertial confinement fusion (ICF) compresses and heats a deuterium-tritium (DT) fuel pellet to thermonuclear conditions using either laser drivers (indirect or direct drive) or pulsed power. NIF’s indirect-drive approach focuses 192 UV beams (1.8 MJ delivered) into a gold hohlraum, generating X-rays that ablate the capsule surface, driving implosion to ~100 g/cc and >10⁸ K. December 2022 ignition shot yielded 3.15 MJ from 2.05 MJ delivered—scientific Q>1 but wall-plug efficiency remains ~0.5%. Focused Energy pursues direct-drive with short-pulse “fast ignition” to relax compression requirements. Key parameters: implosion velocity >400 km/s, hot-spot pressure >350 Gbar, areal density ρR >1 g/cm².
Competitive landscape
| Approach | Driver | Rep-rate path | Key challenge |
|---|---|---|---|
| ICF (NIF/Focused Energy) | High-power laser | Diode-pumped solid-state | Driver efficiency <10%; target cost |
| Magnetic confinement (tokamak) | Magnetic coils | Continuous burn | Plasma stability, tritium breeding |
| Magnetized target (TAE, HB11) | Pulsed compression | Moderate | Intermediate physics risk |
Companies using
Connected ideas
Sources
Frontier (open questions)
- To be added.