Celebrating the life and career of Dick Lee, a trailblazer in high energy density science

Richard W. Lee—known to friends and colleagues as Dick—spent more than five decades making significant contributions to plasma physics and high energy density science. From his early training in spectroscopy to his leadership at Lawrence Livermore National Laboratory (LLNL) to his pioneering work with fourth-generation x-ray free electron lasers, his contributions reshaped how the scientific community understands and explores matter under extreme conditions.

Lee was born in New York City and completed his undergraduate studies at Johns Hopkins University in Baltimore, Maryland, before earning his Ph.D. in physics from the University of Florida in Gainesville in 1970. He then joined the spectroscopy group of the Blackett Laboratory at Imperial College London as a postdoctoral research associate, a position he held from 1970 to 1973.

In 1974, he was appointed lecturer in the same group, where he trained undergraduate and graduate students in plasma spectroscopy and led laser plasma experiments at the Rutherford Central Laser Facility and on the Z-pinch machine at Imperial College, as well as laser-induced fluorescence experiments. It was here that he laid the technical and intellectual foundations that would define his career.

Lee joined LLNL in 1982, and over the following decades took on a succession of leadership roles: group leader and associate division leader for high temperature theory, project leader for physics research at the Janus Laser Facility, and program leader for applied physics. He later served as a senior scientist responsible for developing scientific efforts in high energy density science (HEDS) both within LLNL and across the broader community.

At LLNL, Lee developed techniques for analyzing the radiative properties of hot, dense laboratory plasmas that are now used worldwide. He focused on radiation physics and the opacity of complex ions in dense plasmas produced by high-energy lasers—work that advanced both theoretical models and experimental interpretation. He also originated several fast and precise computational codes designed to be used by experimentalists and theorists alike.

“Dick’s passion for LLNL and HEDS was infectious. Talking to him and listening to his talks drew me towards HEDS and warm dense matter physics in particular,” said Frank Graziani, director of LLNL’s HEDS Center.

One of Lee’s most lasting contributions during his LLNL years was his early and influential advocacy for expanding the NOVA laser’s science program beyond fusion. This effort helped establish what is now known as high energy density physics as a distinct and thriving scientific discipline. He was equally forward-looking on national security applications, becoming an early champion of developing national security programs on the first petawatt laser, NOVA—efforts that helped motivate support for what would become the National Ignition Facility. Lee also played a key role in connecting LLNL with outstanding scientists at Imperial College, many of whom later joined the Laboratory.

“The beginning of the motivation for lasers and pulsed power facilities to support science-based stockpile stewardship owes much to Dick’s advocacy and passion to broaden the science to include topics such as radiation physics that are important to national security,” noted Mike Campbell, former associate director for lasers at LLNL.

In the 1990s, as the U.S. developed its plan for science-based stockpile stewardship—a framework for maintaining the nuclear arsenal in the absence of explosive testing—Lee was working closely with the University of California (UC), Berkeley. Recognizing that the program's long-term success depended on a pipeline of trained scientists, he brought UC faculty to the Department of Energy (DOE) in Washington, D.C. to encourage funding of research and graduate students at universities. The program that resulted continues to this day.

Lee later became associate director of the Institute for Material Dynamics at Extreme Conditions at UC Berkeley, where he led the development of research programs in the science of materials at high energy density—often referred to as warm dense matter. Working in close partnership with Stanford University and the SLAC National Accelerator Laboratory, he pioneered research into materials in extreme conditions using fourth-generation free electron X-ray lasers in the U.S. and Germany.

“Dick Lee was a strong leader at Livermore who recognized the potential to develop X rays into high-precision probes that are now routinely used on the National Ignition Facility as X-ray backlighters and in laboratories around the world using X-ray free electron lasers,” observed Stanford University Professor and SLAC High Energy Density Science Division Leader Siegfried Glenzer.

Lee served on SLAC's Linac Coherent Light Source (LCLS) science advisory committee, authored the warm dense matter and plasma physics chapter of the LCLS first experiments document and presented the case for high energy density science to DOE’s Basic Energy Sciences advisory committee at the meeting that endorsed the LCLS. He was the driving force behind the creation of the Matter in Extreme Conditions end station at LCLS, and in the years leading up to his retirement, joined SLAC/LCLS as head of the science and research division.

“The highlight of the LCLS user meetings in anticipation of first light was Lee’s presentation on the opportunities for high energy density science,” recalled Jerome Hastings, emeritus Stanford University professor. “He always began with ‘all of you will be doing high energy density science, you just don’t know it.’ His vision was prescient.”

Lee contributed to the broader research community not only through his science but through his editorial stewardship. He served as associate editor of the Journal of Quantitative Spectroscopy and Radiative Transfer and later founded and edited the journal High Energy Density Physics. The journal became an important venue for the field he helped create.

Over the course of his career, Lee authored roughly 400 peer-reviewed scientific papers, which have received more than 10,000 citations. He was elected a fellow of the American Physical Society in 1997 and received the John Dawson Award in 2015. In 2021, Aix-Marseille University awarded him the title of Doctor Honoris Causa, one of the highest honors a university can bestow.

Lee passed away on January 31, 2026. His career stands as a model of how a single scientist, through a combination of technical depth, strategic vision and genuine generosity toward colleagues and students, can help shape an entire field. The techniques he developed, the institutions he helped build and the scientists he mentored are his enduring contributions to the international scientific community.

Contributions to this career retrospective were provided by Joseph Kilkenny (General Atomics); Frank Graziani and Steve Libby (LLNL); Siegfried Glenzer and Jerome Hastings (Stanford University); Roger Falcone (UC Berkeley); and Michael Campbell (UC San Diego and MCM Consultants).