Neville C. Luhmann, Jr.

In Memory of Prof. Neville C. Luhmann, Jr.

Neville C. Luhmann Jr., a Distinguished Professor at the University of California, Davis and a towering figure in the fields of plasma physics and vacuum electronics, died on Sept. 5, 2025. He was 82. 

Prof. Luhmann was a mentor, visionary leader, and world-renowned scientist whose work helped to shape modern high-frequency electronics. He began his academic journey at the University of California, Berkeley, where he earned a Bachelor of Science degree in engineering physics in 1966. He went on to receive his Ph.D. in physics from the University of Maryland, College Park, in 1972.  Following a postdoctoral research associate position at the Princeton University Plasma Physics Lab, he launched his academic career at UCLA in 1973. There, over a distinguished 20-year tenure, he ascended from assistant professor to full professor.  

At UCLA, Prof. Luhmann founded and directed the Center for High Frequency Electronics and served as co-director of the Joint Services Electronics Program in Millimeter Wave Electronics. His ability to lead complex, multi-institutional research was evident in his role as program director for several critical Department of Defense Multidisciplinary University Research Initiatives (MURI), focusing on high-energy microwave sources and vacuum electronics. 

Prof. Luhmann joined UC Davis in 1993 and was appointed in 2003 to Distinguished Professor, one of the highest honors bestowed upon a faculty member. He co-directed the Davis Millimeter Wave Research Center and expanded his research on fusion plasma diagnostics. His international acclaim was evident through his roles as an ITER Scientist Fellow and his membership on academic committees for major international research institutions. 

Prof. Luhmann is primarily known for his contributions to Vacuum Electronics in three major areas: (1) the development and application of millimeter wave imaging techniques and their use in core MHD and fluctuations studies in magnetic fusion plasmas; (2) microfabricated THz vacuum electron beam devices; and (3) high power gyro-traveling wave tubes. He is perhaps best known for his research and development in high power gyro devices and sheet beam klystrons. He demonstrated the first frequency multiplying gyro-device in 1990, developed the first harmonic gyro-TWT in 1995, and led in the development of novel sheet beam klystrons at frequencies up to 94 GHz. He has developed a W-band gyro-TWT for the 92-100 GHz Haystack Ultra-wideband Satellite Imaging Radar. His research work has focused on the device physics and led to considerable progress in the suppression of the absolute instability and thus high-power operation as required by the radar community.

A prolific author of approximately 420 journal articles and 18 books, Prof. Luhmann’s contributions were celebrated by many awards in his field. These included the Robert L. Woods/DoD Award, the IEEE John R. Pierce Award for Excellence in Vacuum Electronics, and the Kenneth J. Button Prize from the Institute of Physics, London.  He was honored with UC Davis’s Distinguished Graduate and Postdoctoral Mentoring Award and the Consortium for Women and Research Outstanding Mentor Award. Prof. Luhmann supervised the graduation of more than 100 Ph.D. and M.S. students. Students and colleagues alike remember him for his unwavering support and intellectual generosity.

Prof. Luhmann was elected a Fellow of the American Physical Society (APS) and a Life Fellow of the Institute of Electrical and Electronics Engineers (IEEE), distinctions that reflect the profound and lasting impact of his work. He will be remembered for his brilliant mind, his commitment to mentorship, and his unwavering work to advancing human knowledge. His passing leaves a profound void in the scientific community, but his legacy will continue to illuminate the path for future generations of researchers. 

Prof. Luhmann. is survived by his wife, Janet Luhmann, and a wide circle of colleagues, students and friends who will carry forward his legacy.