What Can Inertial Confinement Do for Materials Science?

Date: Oct. 15, 2026
Speaker: Dr. Yun Kai
Affiliation: Cambridge Heavy Industries and a postdoctoral associate at MIT

Abstract:

Fusion powers the stars and drives the synthesis of many of the elements in the universe. But reproducing fusion on Earth is remarkably difficult. In the first half of this talk, I will introduce the basic physics of fusion from an intuitive perspective: why fusing light nuclei releases energy, why fusion fuel must become a plasma, how quantum tunneling allows nuclei to penetrate their electrostatic repulsion barrier, and why deuterium-tritium is the preferred fuel for most near-term fusion experiments.

I will then introduce the central challenge of fusion: creating a plasma that is simultaneously hot, dense, and confined long enough for fusion reactions to become self-heating. This leads to two very different approaches. Magnetic confinement fusion uses a relatively low-density plasma confined for a long time, while inertial confinement fusion compresses a tiny amount of fuel to enormous density and pressure for only a fraction of a nanosecond. Recent inertial confinement experiments have demonstrated burning plasmas and ignition, showing that laboratory fusion can enter a regime where fusion products substantially heat the fuel themselves.

In the second half of the talk, I will discuss what may come next for inertial fusion. I will describe our work at Cambridge Heavy Industries, a recent spinout from the Nelson Lab at MIT, on compact laser-driven fusion, including synchronized shock compression and staged fast ignition. I will discuss some of the scientific and engineering questions that arise when turning a fusion experiment into a technology, and conclude with lessons from building a fusion startup: how fundamental physics, engineering, capital, and near-term applications can come together in the effort to make fusion useful.