Jongsoo Yoo pursues his passion as deputy head of Discovery Plasma Science

Newswise — Nearly 10 years ago, Wall Street giant Citigroup invited plasma physicist Jongsoo Yoo to discuss a finance position. But the freshly minted Princeton graduate student turned down the invite and decided to remain a postdoctoral researcher at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL). “I believed that plasma physics was more suitable for me,” he recalled, “and I can do science better than finance.”

That proved to be a wise decision. Earlier this year, Yoo was named deputy head of the Discovery Plasma Science (DPS) Department. The newly created unit, spun off from the former Plasma Science & Technology Department, covers broad uses and behavior of plasma, the charged state of matter that makes up 99% of the visible universe.

“I’m thrilled that Jongsoo agreed to serve as DPS Deputy Department Head,” said Erik Gilson, the principal research physicist who heads the department. “When you couple his deep understanding of what PPPL is all about with his enthusiasm for research and his desire to reduce barriers to carrying out safe and effective work, it’s clear that Jongsoo is the right person for the job.”=

Northern Lights
His oversight includes FLARE, the department’s largest facility, which is scheduled to become the most powerful device for studying magnetic reconnection when its installation is finished and it begins operating next year. Reconnection occurs throughout the universe and causes the magnetic field lines in plasma to snap apart and reconnect, producing Northern Lights, solar flares, and geomagnetic storms that can disrupt cell phone service, damage satellites and blackout power grids.

“Jongsoo is leading the creation of a full suite of FLARE diagnostics right now and will lead the upcoming commissioning process and serve as chief operator,” said Princeton professor and PPPL physicist Hantao Ji, principal investigator of experiments planned for the device. The collaborative facility will partner with national and international institutions to probe aspects of magnetic reconnection never before accessible to laboratory experiments.

Yoo’s duties include ensuring the safety and efficiency of the entire department. DPS relies largely on high-powered devices that reproduce cosmic processes ranging from the birth of planets and stars to the origin of supernova shockwaves and must be carefully controlled.

Modifying procedures
His goals include modifying some procedures for small projects at PPPL. “Take a printed circuit board, for example,” he said. “If we order one without a costly review and the design doesn’t work, we can revise the design and go on. So for small projects of low risk under a certain dollar value, we should consider this kind of exception.”

Yoo was born and raised in South Korea and earned his bachelor’s degree summa cum laude from the prestigious Pohang University of Science and Technology. He spent his mandatory military service as a driver for a U.S. lieutenant colonel over a two-year period. He developed solid English skills during that time, which he said gave him more options for pursuing a career path.

That path brought him to Princeton University to study fusion. He had earned a master’s degree in astrophysical sciences when a timely suggestion from Hantao Ji turned him toward magnetic reconnection, which became his research passion. “That was the moment I changed my career,” he said of the advice. He still does some work on fusion for the Korea Superconducting Tokamak Advanced Research (KSTAR) Project with which PPPL collaborates, “but I’m very happy about my conversion.”

His KSTAR collaboration ranges from designing diagnostics for the superconducting tokamak to joining magnetic research experiments.

Progress on FLARE
Yoo now divides his time between FLARE, KSTAR and his DPS deputy role. “I see daily progress on FLARE construction, and we’re targeting next April or May for the start of operation,” he said. Recent FLARE installations have included a capacitor bank that stores and delivers energy, with the installation of AC power and a data acquisition system currently ongoing. Still to come is work ranging from the insertion of diagnostics to the fabrication of mechanical supporting structures.

Outside of the Lab, Yoo runs the Sunday school at his church and participates in the annual stream cleanups of the Watershed Institute of Pennington, New Jersey. He enjoys spending time with his wife and two sons, aged 2 and 9.

After he bought a house, yard work became his newest hobby. “There is still a lot to learn,” he said. “I welcome any advice related to how to keep the lawn neat.”

His interest in science has evolved over the years. “When I was young, I was really wondering why the universe was this large,” he said. “As I got older, fusion drew my attention, as it could be the true solution to the energy problem. Now, I am humble and would be happy to contribute a little to our understanding of Mother Nature.”