CSU scientists create micro-scale nuclear fusion in lab laser experiment

Thursday March 15, 2018 0 comments Tags: Fort Collins, CSU, Jorge Rocca, Alden Curtis


FORT COLLINS -- Nuclear fusion, the process that powers the sun, happens when nuclear reactions between light elements produce heavier ones.CSU_logoUSE_1

It’s also happening -- at a smaller scale -- in a Colorado State University laboratory.

Using a compact but powerful laser to heat arrays of ordered nanowires, CSU scientists and collaborators have demonstrated micro-scale nuclear fusion in the lab.

They have achieved record-setting efficiency for the generation of neutrons -- chargeless sub-atomic particles resulting from the fusion process.

Their work is detailed in a paper published in Nature Communicationsand is led by Jorge Rocca, University Distinguished Professor in electrical and computer engineering and physics. The paper’s first author is Alden Curtis, a CSU graduate student.

Laser-driven controlled fusion experiments are typically done with multi-hundred-million-dollar lasers housed in stadium-sized buildings, CSU said. Such experiments are usually geared toward harnessing fusion for clean energy applications.

In contrast, Rocca’s team of students, research scientists and collaborators work with an ultra-fast, high-powered tabletop laser they built from scratch.

They use their fast, pulsed laser to irradiate a target of invisible wires and instantly create extremely hot, dense plasmas -- with conditions approaching those inside the sun. These plasmas drive fusion reactions, giving off helium and flashes of energetic neutrons.

In their Nature Communications experiment, the CSU team produced a record number of neutrons per unit of laser energy -- about 500 times better than experiments that use conventional flat targets from the same material.

Their laser’s target was an array of nanowires made out of a material called deuterated polyethylene. The material is similar to the widely used polyethylene plastic, but its common hydrogen atoms are substituted by deuterium, a heavier kind of hydrogen atom.

The efforts were supported by intensive computer simulations conducted at the University of Dusseldorf (Germany), and at CSU.

CSU said making fusion neutrons efficiently, at a small scale, could lead to advances in neutron-based imaging, and neutron probes to gain insight on the structure and properties of materials. The results also contribute to understanding interactions of ultra-intense laser light with matter.

The paper is titled “Micro-scale fusion in dense relativistic nanowire array plasmas.” The research was supported by the Air Force Office of Scientific Research and by Mission Support Test Services, LLC.