Swiss-born American physicist. He won the 1952 Nobel Prize in Physics for his nuclear induction method, which he developed to measure the magnetic field of the atomic nucleus.
He was born on October 23, 1905, in Zurich, Switzerland. Bloch, who started his education at the Swiss Federal Technical Institute in Zurich to become an engineer, later became interested in physics and transferred to the University of Leipzig in Germany.
He received his doctorate in 1928 with his thesis on metallic conduction. After working with leading physicists in various European countries such as the Netherlands, Denmark, and Italy, he returned to the University of Leipzig and served as a lecturer from 1932-1933. Bloch, who left this country after Hitler came to power in 1933, settled in the USA and took a position as a professor at Stanford University.
Felix Bloch (23 October 1905 – 10 September 1983) was a Swiss-American physicist and Nobel physics laureate who worked mainly in the U.S. He and Edward Mills Purcell were awarded the 1952 Nobel Prize for Physics for "their development of new ways and methods for nuclear magnetic precision measurements." In 1954–1955, he served for one year as the first Director-General of CERN.
Bloch became a naturalized US citizen in 1939. During World War II, he worked at the Radio Research Laboratory at Harvard University on the atomic bomb project at Los Alamos.
Returning to his job at Stanford after the war, he focused his physics studies on the magnetic fields of atomic nuclei. In 1945 he developed the principle of nuclear induction and studied the relationship between the crystalline and magnetic properties of matter and nuclear magnetic fields. In 1952, he shared the Nobel Prize in Physics with E. M. Purcell, who had discovered the same principle in an independent study.
Felix Bloch, who was elected to the US National Academy of Sciences in 1948, was the first director of CERN (European Nuclear Research Council) in Geneva between 1954-1955. He retired in 1971 and received the title of Emeritus Professor.
The event that sparked his interest in the subject of nuclear magnetic resonance, to which Felix Bloch contributed significantly, was in 1933 when O. Stern found that the magnetic moment of the proton was three times what was expected, thus it was understood that the neutron in the deuterium (heavy water) nucleus also contained a magnetic moment.
Bloch suggested in 1936 that this property could be used to polarize neutron beams by passing them through magnetized iron. In 1939, he combined this effect and the radio technique previously applied to atomic rays, and together with Luis Alvarez, he succeeded in accurately measuring the magnetic properties of the neutron. He then considered using the radio technique as an electromagnetic method that could be applied not only to particle beams but also to normal matter.
Making use of this method in 1946, Felix Bloch, W. W. Hansen, and M.E. Working independently of the protons in Packard water, Purcell and his research team observed nuclear magnetic resonance (NMR) phenomena in protons in dc paraffin. Felix Bloch held the sample used for measurement under the influence of a strong electromagnet, causing the core magnetic moments to change in the direction of the magnet's constant magnetic field with a radio transmitter. This change created a voltage in a wire wound on the matter, according to Faraday's principle of electromagnetic induction. Detection of this nuclear induction with a radio receiver provided important information about the magnetic moments and angular momentums that later illuminated the nuclear structure of the nuclei, as well as allowed the analysis of isotopes of the same element that cannot be separated chemically because they are formed from nuclei of different structures.
Felix Bloch's work has enabled the determination of the structural and magnetic properties of various substances by using nuclear magnetic fields, and a better understanding of the structure and properties of molecules.