The 1994 Nobel Prize in Physics was awarded “for pioneering contributions to the development of neutron scattering techniques for studies of condensed matter.” The award was split jointly between Bertram N. Brockhouse “for the development of neutron spectroscopy” and Clifford G. Shull “for the development of the neutron diffraction technique.”
The Science: Neutron Scattering
Creating methods for studying small objects in detail has long been an interest in science, and new advances in these technologies have helped drive the scientific endeavor forward.
Microscopes allow for the enhancement of visual light images, and these can be modified to include X-Ray techniques that magnify at a range greater than what can be seen in visible light.
The science recognized in this Nobel Prize was developed after World War II, using the nuclear reactors that were available at that time to harness the emitted neutrons and use them to study the behavior of atoms, by measuring how the neutrons deflect off of the atoms (a process called neutron scattering). This method is useful because neutrons are electrically neutral, so do not have any electromagnetic interactions with the protons or electrons of an atom. The official 1994 Nobel Prize of Physics press release has a particularly useful and concise description of this process:
When the neutrons bounce against (are scattered by) atoms in the sample being investigated, their directions change, depending on the atoms’ relative positions. This shows how the atoms are arranged in relation to each other, that is, the structure of the sample. Changes in the neutrons’ velocity, however, give information on the atoms’ movements, e.g. their individual and collective oscillations, that is their dynamics. In simple terms, Clifford G. Shull has helped answer the question of where atoms “are” and Bertram N. Brockhouse the question of what atoms “do”.
Bertram N. Brockhouse
Bertram N. Brockhouse was born on July 15, 1918, in Lethbridge, in the province of Alberta, Canada, though his family moved to Vancouver, British Columbia, in 1926 and that’s where he grew up (except for a brief stint in Chicago from 1935 to 1938). After some time in the military during World War II, Brockhouse proceeded to study Physics and Mathematics at the University of British Columbia. During this time he worked as a government scientist at the Chalk River Laboratory. He completed his PhD work in fall of 1950, and he performed the neutron scattering work that would earn him the Nobel Prize throughout the early 1950’s. Brockhouse joined the faculty of McMaster University, in Hamilton, Ontario, as a Professor of Physics in 1962.
Bertram Brockhouse died on October 13, 2003, in Hamilton, Ontario.
Clifford G. Shull
Clifford G. Shull was born on September 23, 1915, in the Glenwood section of the city of Pittsburgh, in the state of Pennsylvania, United States of America. For college, he attended the Carnegie Institute of Technology (later renamed to Carnegie Mellon University) for his undergraduate degree, then went on to graduate school at New York University in 1937. He completed his work to earn his doctorate in physics in June 1941.
Having earned his doctorate, he proceeded to Beacon, NY, for a research laboratory job with The Texas Company. His company would not release him for work on the Manhattan Project during World War II. After the war was over, Shull and his family moved to the Clinton Laboratory in Tennessee, where he performed a great deal of neutron diffraction research along with his colleague Ernest Wollan. He left Tennessee in 1944 to join the faculty at the Massachusetts Institute of Technology (MIT), where he remained until his 1986 retirement.
Clifford Shull died on March 21, 2001, in Medford, Massachusetts.