Hans Georg Dehmelt
Dehmelt, Hans Georg (1922-) is a German-born American physicist. He shared the 1980 Nobel Prize in physics with German physicist Wolfgang Paul and American physicist Norman Foster Ramsey for devising a method for capturing and holding single electrons for extended periods of time. Paul was Dehelt's former professor.
Dehmelt was born in Görlitz, Germany. In 1940, during World War II (1939-1945), Dehmelt left the Berlin Gymnasium and joined the German Army. He returned to Germany in 1943 to study physics at the University of Breslau, but then returned to active duty and was captured in the Battle of the Bulge in 1944. In 1946, after his release, Dehmelt studied physics at Göttingen University under Wolfgang Paul. He received his doctorate in 1950. While he was preparing his thesis, he worked on mass spectrography. He later studied nuclear magnetic resonance (NMR). In 1949, he discovered a related form of magnetic interaction, nuclear quadruple resonance (NQR).
In 1952, Dehmelt traveled to the United States. He was a faculty member at Duke University in North Carolina through 1955 and then accepted a position at the University of Washington. He became a full professor in 1961. In 1962, he became a U.S. citizen.
Dehmelt is best known for finding ways of capturing free electrons and ions using electric and magnetic fields. He was able to keep the electrons or ions trapped for about 10 seconds, which gave him time to study their properties. In 1973, he succeeded in isolating a single electron. He was the first scientist to do so. With his colleagues, he was also able to isolate various ions and positrons. Dehmelt also developed a way of cooling a single trapped electron in 1976, a technique that improved the accuracy of measurements. For his particle-trapping work, Dehmelt shared the 1989 Nobel Prize in physics.