What is magnetized target fusion?

How it works

Magnetized target fusion sits between the two main lines of fusion research. A 2019 retrospective of a program run by ARPA-E, the U.S. Department of Energy's advanced research agency, explains the gap. It was published in the Journal of Fusion Energy. ITER, a magnetic confinement machine, will hold a low-density plasma in long pulses. The National Ignition Facility is a pulsed device that compresses fuel targets to extreme density. ARPA-E's program focused on the densities in between.

The paper describes the shared idea. A magnetized plasma, the "target," is compressed in a pulse by a "driver." That raises its density and temperature. The paper uses the name magneto-inertial fusion and says it is sometimes called magnetized target fusion. In this approach, the driver is an imploding liner that conducts electricity. The authors said the little-explored middle range offered a chance of lower development costs.

General Fusion's LM26

General Fusion, a Canadian company, is developing the approach. Its LM26 machine compresses a plasma inside a solid lithium liner that starts 1.76 meters across, according to a company paper. Coils implode the liner.

The squeeze takes milliseconds, the UK Atomic Energy Authority says. Other compression methods work in microseconds or nanoseconds. The design avoids superconducting magnets and high-powered lasers. General Fusion argues that the slower pace means less power, less complexity and lower cost.

On October 8, 2026, the company and UKAEA said LM26 had heated plasma electrons past 1 keV, to more than 12 million degrees Celsius. The papers were submitted for peer review. The company's next targets are 10 keV and then the Lawson criterion, the conditions for net fusion energy in the plasma. The company's chief executive wrote that it targets the Lawson criterion by the end of 2028.

From experiment to power plant

A power plant would need a different wall. General Fusion plans a liquid metal wall that it says would shield the machine from neutrons, breed fuel and capture heat to make steam. TechCrunch reported in July 2026 that the company says mechanical drivers would force the liquid lithium inward around the plasma. No such plant exists. The company aims to begin operating its first one around 2035.