John Joseph Hopfield (born Jan Józef Chmielewski; July 8, 1891 – January 8, 1953) was a Polish-American physicist. Hopfield's published research included vacuum ultraviolet spectroscopy and solar ultraviolet spectroscopy. He was the discoverer of the "Hopfield bands" of oxygen and co-discoverer of the "Lyman–Birge–Hopfield bands" of nitrogen. For about a decade he was an industrial physicist working with technologies for fabricating glass windows, and was the inventor listed on several related patents.[1][2][3][4]
Career
Born in Poland, little is known about Hopfield's upbringing. He was admitted to Syracuse University around 1913, and completed his A.B. degree in 1917 and then worked as an instructor through 1919. At Syracuse, he had worked as an assistant with Raymond Thayer Birge, who moved to University of California, Berkeley around this time. Hopfield was then admitted to Berkeley with a fellowship, and was awarded his doctorate for spectroscopic work in 1923. He became an instructor and assistant professor of physics at Berkeley, and was awarded a Guggenheim Fellowship in 1928 to work with Friedrich Paschen for a year in Berlin.[1]
By the time he left Berlin in 1929, the stock market crash and depression had ended most new faculty hiring. Purdue University appointed him as a National Research Council Fellow for two years. He next was employed in creating the physics exhibit for the 1933 "Century of Progress" World's Fair in Chicago. This was followed by a position with the Libbey-Owens-Ford glass company in Toledo, Ohio. With the onset of the Second World War, physicists were again in great demand, and he moved to Washington, D.C., to participate in war-related research. The end of his career was spent at the Johns Hopkins University Applied Physics Laboratory and at the Naval Research Laboratory in the Optics Division in Washington, D.C.. On January 8, 1953, Hopfield died after a brief illness.[5]
Method of fabricating multiple glass sheet glazing units[19]
References
^ abBirge, Raymond Thayer (1966). History of the Physics Department. University of California, Berkeley. pp. 15–18. OCLC6494379. Birge devoted several pages of this manuscript to Hopfield.
^Ajello, Joseph M. (March 2020). "The UV Spectrum of the Lyman-Birge-Hopfield Band System of N2 Induced by Cascading from Electron Impact". Journal of Geophysical Research: Space Physics. 125 (3). Bibcode:2020JGRA..12527546A. doi:10.1029/2019JA027546. S2CID213340934.
^"John J. Hopfield". Physics Today. 6 (3): 24. 1953. doi:10.1063/1.3061184. John J. Hopfield, physicist at the optics division of the Naval Research Laboratory at Bethesda, Maryland, died after a brief illness on January 8th at the age of sixty‐one.
^Hopfield, John J. (28 February 1933). HOPFIELD. Vol. U.S. Patent No. 1, 899, 804. Washington, D.C.: U.S. Patent and Trademark Office.
^Hopfield, John J. (3 September 1940). Manufacture of multiple glass sheet glazing units. Vol. U.S. Patent No. 2, 213, 395. Washington, D.C.: U.S. Patent and Trademark Office.
^Hopfield, John J. (14 January 1941). Uniting of glass to glass and metals to glass. Vol. U.S. Patent No. 2, 228, 352. Washington, D.C.: U.S. Patent and Trademark Office.
^Haven, Charles D.; John J. Hopfield (18 March 1941). Multiple glass sheet glazing unit and method of making the same. Vol. U.S. Patent No. 2, 235, 680. Washington, D.C.: U.S. Patent and Trademark Office.
^Haven, Charles D.; John J. Hopfield (18 March 1941). Multiple glass sheet glazing unit. Vol. U.S. Patent No. 2, 235, 681. Washington, D.C.: U.S. Patent and Trademark Office.
^Hopfield, John J. (14 December 1943). Method of fabricating multiple glass sheet glazing units. Vol. U.S. Patent No. 2, 336, 544. Washington, D.C.: U.S. Patent and Trademark Office.