Willis Eugene Lamb, Jr.

Willis Eugene Lamb, Jr. (1913-2008), American physicist and Nobel Prize winner. Lamb made groundbreaking discoveries about the energy states of the hydrogen atom. Lamb and German-born American physicist Polykarp Kusch shared the 1955 Nobel Prize in physics for their independent research.

Born in Los Angeles, California, Lamb completed his B.S. degree in chemistry at the University of California, Berkeley, in 1934 and stayed on to receive his Ph.D. degree in physics in 1938. He went on to be an instructor (from 1938 to 1948) and professor (from 1948 to 1951) in physics at Columbia University in New York City. He was a professor of physics at Stanford University in California from 1951 to 1956, at the University of Oxford in England from 1956 to 1962, and at Yale University in New Haven, Connecticut, from 1962 to 1974. In 1974 Lamb became a professor of physics at the University of Arizona in Tucson.

Lamb is best known for his accurate studies of the hydrogen spectrum’s hyperfine structure, which reveals that there can be tiny differences in energy between two atoms in the same energy level (see Spectroscopy: Spectrum Lines). In 1947, through sophisticated measurements, he showed that the two possible energy states of hydrogen differed by a very small amount. This contradicted earlier predictions by English physicist Paul Dirac that these energy states were equal. Lamb’s discovery is called the Lamb shift. The shift required physicists to revise their understanding of the interaction of the electron with electromagnetic radiation. The effect was caused by virtual particles that pop in and out of existence in empty space according to quantum mechanics theory, slightly affecting the orbits of the electrons in the atom.

Lamb also contributed significantly to the study of theoretical physics, atomic and nuclear structure, microwave spectroscopy, and maser and laser physics. Lamb later conducted research on theoretical atomic physics and quantum optics at the University of Arizona as a professor of physics and optical sciences.

Lamb was elected to the National Academy of Sciences in 1954. He was awarded the National Medal of Science in 2000. The annual Willis E. Lamb Award for Laser Science and Quantum Optics was created in his honor in 1998.