Bertram Neville Brockhouse , 1918-2003
Bertram Brockhouse, one of the world's greatest scientists, died on October 13, 2003, at the age of 85. His brilliant pioneering work, carried out at the Chalk River Nuclear Laboratories during the period 1950 to 1962, laid the foundations for the immensely powerful field of neutron inelastic scattering that is now employed by many thousands of scientists in universities, in industry and in government laboratories worldwide. Neutron scattering techniques have a wide range of applications in condensed matter physics, materials science, geology, biology, ceramics, polymer science and in industrial manufacturing. The fundamental importance of Dr. Brockhouse's achievements has been recognized by many prestigious awards and honours, including the 1994 Nobel Prize in Physics, which he shared with Clifford Shull of the United States.
Dr. Brockhouse, or Bert, as all his friends and colleagues called him, was born in Lethbridge, Alberta, in 1918, and spent much of his youth and received most of his schooling in Vancouver. After leaving high school, Bert became interested in radio technology and for a few years worked in this field, just before the outbreak of World War II. With this experience, he joined the Canadian Navy in 1939 as a radio technologist, spent some months at sea but much of the wartime as a shore-based ASDIC (Anti-Submarine Detection Investigation Committee) repairman. In 1944 he enrolled in a six-month course in electrical engineering at Nova Scotia Technical College and then, as a newly-minted electrical sub-lieutenant, was assigned to the test facilities at the National Research Council (NRC) in Ottawa. It was there that he met Doris Miller, a truly wonderful person who later (in 1948) became his wife and lifelong supporter.
After the war, Bert was able to resume his education, and he obtained a Bachelor's degree in mathematics and physics at the University of British Columbia, followed by a PhD in physics at the University of Toronto, in 1950. Then, in a most significant turn of events, he accepted a position offered to him by Donald Hurst to do research in NRC's Atomic Energy Project at Chalk River (which in 1952 became Atomic Energy of Canada). Don Hurst and colleagues had already built a primitive neutron spectrometer at the NRX reactor at Chalk River, and Don encouraged Bert to "look into what research could be done with neutrons". In 1951, Bert realized that certain fundamental properties of solids - the so-called phonon dispersion curves, from which the interatomic forces could be deduced - could in principle be studied by measuring the inelastic scattering of slow neutrons, and that such measurements might be possible with the neutron beams available from NRX. Over the next few years, Bert developed several types of neutron spectrometers, such as the beryllium filter and the rotating crystal spectrometers. He continuously improved the performance of all their components (monochromator crystals, filters, collimators, detectors) so as to increase the overall neutron detection efficiency. His efforts culminated in the now world-famous "Triple-Axis Crystal Spectrometer" and the "Method of Constant-Q" which launched the new field of neutron inelastic scattering as an extremely powerful tool in the study of condensed matter (solids and liquids).
In 1955, with an early version of the TACS mounted at the NRX reactor, and with the able assistance of Alec Stewart, Bert successfully measured the phonon dispersion curves of aluminum, thereby confirming that phonons really did exist in metals. By 1957, the TACS development was essentially complete, and with the greatly increased neutron intensities available from the newly built NRU reactor (the best research reactor in the world at that time), Bert was able to apply his amazing inventions to a highly successful study of fundamental problems in condensed matter science. In quick succession, he and his co-workers produced ground-breaking papers on phonons in metals (sodium and lead, in addition to aluminum), semiconductors (germanium, silicon), salts (sodium iodide, potassium bromide), on spin waves in magnetic materials (magnetite, cobalt) and on diffusive molecular and atomic motions in liquids (light and heavy water, liquid lead). The scientific significance of these experiments, the power and precision of the TACS and method of constant-Q, and the superb intuition that underpinned Bert's achievements, can hardly be over-emphasized.
Bert Brockhouse's work brought him many awards and honours, including the Buckley Prize of the American Physical Society, the Duddell Medal of the UK Institute of Physics, the Medal for Achievement in Physics of the Canadian Association of Physicists, the Tory Medal of the Royal Society of Canada, and the Nobel Prize for Physics. He is the 14th Canadian to have won the Nobel Prize, and only the second Canadian-born scientist to win the Nobel for work done in Canada. (The first was Frederick Banting, for medicine, in 1923). He was a Companion of the Order of Canada, and a Fellow of the Royal Societies of Canada and London.
Teaching students in a university setting had always attracted Bert, and in 1962, he accepted a professorship at McMaster University in Hamilton. He and his wife Doris and six children soon settled in nearby Ancaster, and he proceeded to give lectures and build neutron spectrometers at the McMaster nuclear reactor. He supervised students (eleven in all) doing their PhD work in neutron scattering and condensed matter science. Several of these students went on to successful scientific careers in their own right.
Bert was a strong supporter of the CAP. Both Bert and the other new Nobel Laureate, Cliff Shull, attended the 50th Anniversary Congress of the CAP at Université Laval in 1995 and gave presentations during the opening ceremonies. Bert also attended the 1999 CAP Congress at the University of New Brunswick, where he was awarded the CAP's first "P.Phys" (see photo), and where he presented the first Brockhouse Medal of the CAP and its Division of Condensed Matter and Materials Physics to Walter Hardy of UBC. Because of failing health, the last Congress he attended was the one at York University in 2000.
During the 1970s, Bert gradually turned his attention to more philosophical aspects of science, leaving further neutron scattering experimentation to the many thousands of researchers who followed in his footsteps in laboratories around the world. He became an Emeritus Professor at McMaster upon his retirement in 1984. Throughout his career, he was always a fine gentleman, a very good friend, a loving husband and father. It was indeed a great honour and privilege to have known him and worked with him. We shall remember with gratitude and affection his warm companionship and his occasional bursts of Gilbert and Sullivan songs.
Gerald Dolling, 2003 December 3.