Research News from the Princeton Plasma Physics Laboratory

Steve Cowley, PPPL director, with students in the graduate Princeton Program in Plasma Physics at PPPL. (Photo by Elle Starkman/PPPL Office of Communications.)

Welcome to Quest

It is my pleasure to welcome you to the 2021 edition of Quest, the annual magazine of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) that highlights our research and development activities over the past year. PPPL is the only one of the 17 DOE national laboratories devoted to the development of fusion energy and the exploration of plasma, the state of matter that makes up 99% of the visible universe and fuels fusion reactions, and are rapidly broadening our research into challenging and exciting new areas. New ventures include building a robust computational science program to understand fusion plasma physics and design fusion facilities, and exploring the synthesis of plasma into nanomaterials for applications from semiconductor manufacturing to super-fast quantum computers and other industrial uses.

Our expansion into a multi-purpose laboratory is outlined in the People section of these pages in descriptions of the two world-class scientists who lead the new efforts. The ventures are part of a major transition that includes enlarging our science and engineering staff, refurbishing our infrastructure, constructing a modern laboratory to replace worn-out buildings, and deepening our rich research collaborations with Princeton University, which has managed PPPL since we opened our doors as Project Matterhorn in 1951.

The past year was rife with breakthroughs as we forged ahead despite difficulties posed by the COVID pandemic. Our prolific and productive research staff has delivered outstanding experimental and theoretical breakthroughs into the scientific basis for producing fusion energy and into plasma disciplines from astrophysics to nanotechnology. In the section New Paths to Fusion Energy we outline how to avoid damaging heat bursts in doughnut-shaped fusion facilities and identify a key source of turbulence that causes crucial heat to leak from fusion plasmas. We also describe a major new venture to develop permanent magnets to simplify stellarators, the Number 1 fusion device behind tokamaks, which operate without the risk of sudden disruptions that tokamaks face.

Meanwhile, repair of the National Spherical Torus Experiment-Upgrade (NSTX-U), our flagship fusion experiment, is strongly advancing in preparation for restarting the world’s most powerful spherical facility.

On the theoretical front we are applying artificial intelligence (AI) to improve the prediction of damaging tokamak disruptions, using some of the same AI technology found in home assistants and commercial smart speakers. Other pieces in the section Advancing Fusion Theory include insight into hiccups that cool fusion plasmas and understanding the behavior of the complex edge of fusion plasmas that will be critical for ITER, the international tokamak under construction in Cadarache, France.

Further outlined in this issue are investigations into the creation of stars and planets and the source of space weather that can disrupt communications satellites as described in Advancing Plasma Science. Among the ventures in Collaborations is a new national center created by PPPL and Princeton University to provide access to U.S. and International researchers to state-of-the-art diagnostics, computational tools, and expertise for characterizing low temperature plasmas, a fast-expanding source of innovation in numerous industries. Included too are Laboratory projects with the Wendelstein 7-X (W7-X) stellarator in Greifswald, Germany, and partnerships with private industry under the DOE’s Innovation Network for Fusion Energy (INFUSE) project to accelerate the development of fusion energy.

You will also find the innovative work of our Science Education Department with students and teachers across the country, as described in Education & Outreach. Included in the Awards & Recognitions section is the lengthy list of honors won by our researchers and graduate students, further evidence of the path-setting quality of PPPL research. New this year is an Upcoming section that focuses on arriving capabilities and projects under way.

As ever, I hope that you enjoy this issue and plan to stay tuned here. Please also feel free to contact me here with any thoughts that you may have; I welcome your feedback and ideas.