Laser-Plasma Jedi Advances Nuclear Nonproliferation

When the Star Wars movie launched in 1977, many around the world became mesmerized by an iconic laser and plasma interaction—lightsabers. Back then, Sivanandan “Hari” Harilal was not one of them. Yet, he would travel the world, learning from experts to hone his skills on this dynamic interaction.

Nearly 50 years later, Harilal, a physicist at Pacific Northwest National Laboratory (PNNL) and a Jedi in laser-produced plasma applications, has been named a member of the Institute of Electrical and Electronics Engineers (IEEE) Class of 2025 fellows.

Meaningful mentorships

Growing up in southern India, Harilal was focused on doing well in school with the sole goal of getting a job. His parents worked as government employees, and with his love of math and physics, they encouraged him to be a high school teacher or college professor. Even as an undergraduate student at the University of Kerala, Harilal had yet to envision a life outside his homeland.

But key mentors transformed his plans and opened the door to new opportunities.

One of the first pivotal moments was touring research laboratories at the end of his undergraduate studies. For the first time, his interest was piqued in possibly becoming a scientist.

That led to the decision to continue his studies. Then, as he was wrapping up his master’s degree, a professor encouraged him to apply and test for the Council of Scientific and Industrial Research Fellowship, a prestigious opportunity that would fund his doctorate degree at any university or government lab in India. After learning of his acceptance, his path to becoming a scientist was clear.

Power of plasma

Lightsabers aside, lasers are ubiquitous—used in everyday items such as checkout lanes at grocery stores, presentation pointers in schools, and DVD players at home. High-powered lasers today are commonly used in manufacturing processes, medical machinery, national security applications for the military, and even the production of nuclear fusion.

Plasma is the fourth state of matter, making up to 99.9 percent of our universe. This plasma state, composed of superheated, ionized gases, is responsible for the sun's intense energy and light output. On Earth, high-powered lasers can be used to generate plasmas in the laboratory. Plasma science and technology enhances various aspects of daily life. Scientists study plasma to better understand matter, supporting goals like achieving fusion energy and improving the manufacturing of semiconductors.

Cochin University of Science and Technology, where Harilal earned his PhD, had one of the most powerful lasers in India.

“As an undergraduate student, visiting several research labs ignited my passion for becoming a scientist,” he said. “In the early days of my research as a PhD student, I explored various topics before discovering my enthusiasm for working with lasers and plasma. This fascinating field captivated me and solidified my commitment to a career in research.”

During his doctoral exams, another professor encouraged him to apply for the Alexander Humboldt Fellowship, which took him to Ruhr University in Germany. As a postdoctoral fellow, his mentor was Professor Hans-Joachim Kunze, a world-renowned plasma physicist, who deepened his expertise in plasma research.

For Harilal, the combination of studying lasers and plasma was fortuitous and thrilling.

Laser focus on nuclear nonproliferation

At PNNL, Harilal’s research centers on laser-plasma applications in the field of nuclear nonproliferation, especially in the context of plasma sources and the detection of radioactive nuclear materials and their isotopes. Since joining PNNL, the majority of Harilal’s research has been funded by the National Nuclear Security Administration.

Detecting nuclear materials can mitigate nuclear terrorism and threats, as well as potentially identify parties who are trafficking illicit materials.

“This research significantly benefits the public and national security,” said Harilal. “Also, we’re developing more efficient sources for photolithography, which is integral to fabricating computer chips, and improving diagnostics that can enhance materials processing and manufacturing.”

One of his latest publications describes how the team demonstrated a new way to detect tritium, a radioactive isotope of hydrogen. In the field, this improves the ability of researchers to detect nuclear materials quickly and with minimal to no sample preparation.

“The ability to analyze and optimize plasma is important for nuclear science and technology,” said Harilal. “My work often focuses on improving diagnostic techniques, such as high-resolution spectroscopy, that enhance our ability to analyze and optimize plasma for various applications, including isotopic analysis and standoff detection.”

Looking back at his career, Harilal sees his most impactful footprint as elevating the understanding of high-powered laser-plasma interactions and expanding their applications for a safer world.

Research recognition

IEEE selects fellows based on their contributions “to the advancement or application of engineering, science and technology, bringing the realization of significant value to society at large.” During his 18 years as an IEEE member, Harilal has served in various roles, including chair of the IEEE International Conference on Plasma Science in 2022 and a guest editor of IEEE Transactions of Plasma Science.

Harilal has published more than 200 peer-reviewed publications on topics such as laser-produced plasma and its applications, actinide spectroscopy, plasma diagnostics, and plasma sources for lithography and microscopy. He feels fortunate to have landed in a field that is quickly evolving and growing. He credits these forces for his continued excitement for future research as he looks to tackle microbeams and light sources for microelectronics next.

The IEEE Fellow honor is in addition to his recognition from the International Society of Optics and Photonics (SPIE). Last year, he was also selected as a SPIE Fellow for his technical achievements and service to the general optics community.