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Swiss-born American physicist Felix Bloch won the Nobel Prize in physics in 1952. Bloch won the prize for his development of high-precision methods in nuclear magnetism and for discoveries stemming from these methods.
Felix Bloch (1905-1983), Swiss-born American physicist, educator, and cowinner of the 1952 Nobel Prize for physics. Bloch shared the Nobel Prize with American physicist Edward Mills Purcell for their development of a new method for the precise measurements of the strength of the magnetic field of the atomic nucleus, called nuclear magnetic resonance (NMR). A number of important applications have come from NMR, including magnetic resonance imaging (MRI). MRI produces detailed internal images of the human body, which helps physicians diagnose disease and injuries.
Born in Switzerland, Bloch studied engineering and physics at the Federal Institute of Technology in Zürich from 1924 to 1927. He received his Ph.D. degree in physics in 1928 from the University of Leipzig, Germany. From 1928 to 1932 he served as a researcher at a number of different universities in Europe and was a professor at the University of Leipzig from 1932 to 1933. Bloch left Germany in 1933 and worked at various institutions in Holland, Denmark, and Italy. He moved to the United States in 1934 after accepting an associate professorship of physics at Stanford University. He became an American citizen in 1939, and held his position at Stanford until his retirement in 1971. During World War II (1939-1945), Bloch worked on the Manhattan Project at Los Alamos (see Nuclear Weapons), contributing to the effort to develop an atomic bomb and to improve radar technology. In 1954 and 1955 he served as the first director-general of the European Organization for Nuclear Research (CERN), the multinational laboratory for nuclear science in Geneva, Switzerland.
In 1945 Bloch lead a team that successfully used a new method to measure the strength of the magnetic field of the nucleus using radio waves and nuclear magnetic resonance (NMR) to perform the measurements. In NMR, scientists can measure how much electromagnetic radiation of a specific frequency is absorbed by an atomic nucleus that is placed in a strong magnetic field (see Magnetism). This method helps to reveal atomic and molecular structures (see Atom). At the same time, Purcell and his research group at Harvard University made similar observations.
Scientists, researchers, and the general public continue to benefit from Bloch's discoveries. NMR revolutionized the field of chemistry and has become the most important spectroscopic (see Spectroscopy) technique in chemistry and biology. Scientists use NMR instruments to determine the moisture content of food, check the quality of drugs and medicines, and probe the nature of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) (see Nucleic Acids), the building blocks of human life.