A hybrid approach that compresses a magnetized plasma target using mechanical or liner implosion — combining elements of magnetic and inertial confinement, pursued commercially by General Fusion.
ReviewedLast reviewed: 9 Aug 2026·Category: Concepts & Physics
The Middle Ground
Magnetized target fusion (MTF), also called magneto-inertial fusion (MIF), occupies the parameter space between magnetic confinement (low density, long confinement time) and inertial confinement (extreme density, nanosecond confinement). MTF compresses a pre-formed magnetized plasma to moderate density (1019–1022/cm³) on microsecond timescales.[1]
Why magnetize? Adding a magnetic field to an imploding plasma suppresses cross-field thermal conduction, reducing the implosion velocity (and energy) needed to reach fusion temperatures by 10–100× compared to un-magnetized ICF. This makes less extreme drivers (pistons, liners) viable instead of multi-megajoule lasers.
Approaches
General Fusion: Uses an array of pneumatic pistons to compress a liquid metal (molten lead-lithium) cavity around a magnetized plasma target. The company has raised over $300 million and is building a Fusion Demonstration Plant in the UK.[2]
MagLIF (Sandia): Uses the Z Machine’s pulsed-power current to implode a cylindrical metal liner around a laser-preheated, magnetized D–D plasma. MagLIF has produced significant fusion neutron yields in experiments.[3]
Challenges
Key challenges include Rayleigh–Taylor instability during compression, plasma–liner mixing, repetition rate for a power plant, and developing targets/liners that can be mass-produced at low cost.
Sources
Lindemuth, I.R. and Siemon, R.E. "The fundamental parameter space of controlled thermonuclear fusion." American Journal of Physics, 77, 407, 2009.
General Fusion. "Technology." generalfusion.com.
Gomez, M.R. et al. "Experimental demonstration of fusion-relevant conditions in magnetized liner inertial fusion." Physical Review Letters, 113, 155003, 2014.