Magnetic confinement (tokamaks) holds a continuous, low-density plasma in place with magnetic fields for seconds at a time. Inertial confinement instead compresses a tiny fuel pellet to extreme density in nanoseconds using converging laser beams, relying on the fuel's own inertia to hold it together just long enough to burn. Both approaches are judged by the energy gain factor Q — fusion energy released divided by energy put in.
Q = E_fusion / E_input
Magnetic breakeven: Q = 1 at n·T·τ ≳ Lawson limit
Inertial ignition: ρR > 0.3–1 g/cm² (areal density of compressed fuel)
- Approach toggle — switches between the tokamak torus (magnetic) and the laser-driven imploding pellet (inertial).
- Input energy — heating power for magnetic confinement, or total laser energy for inertial; more input drives higher fusion yield but must be recouped for Q > 1.
- Fuel density — background plasma density (magnetic) or pellet compression factor (inertial); higher density strongly boosts reaction rate.
- Fire / Reset shot — restarts an inertial-confinement laser shot, or resets the magnetic plasma buildup.
ITER pursues the magnetic route toward Q > 10, while the NIF facility demonstrated inertial-confinement ignition (Q > 1 at the target) in 2022 — this sim lets you compare both strategies' engineering trade-offs directly.