Daniel Kleppner
About Optica
In Memoriam: Daniel Kleppner, 1932-2025
16 June 2025
Daniel Kleppner, Optica Fellow and recipient of the Frederic Ives Medal/ Jarus W. Quinn Prize (2007), passed away on 16 June 2025 at the age of 92. Kleppner was known for his experimental atomic physics research and pioneering work on Bose-Einstein condensation (BEC). Optica recognized him for his outstanding contributions to spectroscopy, including the development of the hydrogen maser, spectroscopy of Rydberg states, and analysis of the interaction of atoms with electromagnetic fields. Kleppner’s research provided the basis for significant advancements such as the global positioning system (GPS), magnetic resonance imaging (MRI), and quantum computing.
Kleppner received his B.A. from Williams College, and a B.A. from Cambridge University in 1955. Under the supervision of Norman F. Ramsey, Kleppner conducted graduate research in physics at Harvard University, where he received his Ph.D. in 1959. Kleppner would later join Dr. Ramsey in the creation of the hydrogen maser, a novel type of atomic clock that was cited in Dr. Ramsey’s 1989 Nobel Prize for Physics. In 1966, Kleppner joined the physics department at MIT. Kleppner’s research interests included precision measurements, fundamental constants, and experimental studies with Rydberg atoms, including cavity quantum electrodynamics and quantum chaos. With his MIT colleague, Thomas J. Greytak, Kleppner helped to pioneer the field of Bose-Einstein condensation and quantum gases. Together in 1998, they demonstrated Bose-Einstein condensation in atomic hydrogen.
Kleppner went on to become one of the founders of a MIT-Harvard joint research lab, the Center for Ultracold Atoms. Kleppner would have a distinguished career at MIT that spanned 37 years, and he held the position of the Lester Wolfe Professor Emeritus of Physics.
Kleppner published extensively during his career, including journal articles and books such as An Introduction to Mechanics and Quick Calculus. Kleppner was the recipient of many awards, including the Lilienfeld Prize (1991), OSA William F. Meggers Award (1991), Wolf Prize in Physics (1991), National Medal of Science (2006), and the Frederic Ives Medal (2007). He was elected to the American Academy of Arts and Sciences (1986), a Fellow of OSA (1992), the French Academy of Sciences (2004), and the American Philosophical Society in 2007.
Optica and the scientific community mourn his loss.
