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Nevill MottEnglish physicist, Nobel Prize laureate in physics in 1977.
Date of Birth: 30.09.1905
Country:  Great Britain |
Content:
- Neville Francis Mott: A Renowned Physicist
- Doctoral Studies and Academic Career
- Solid State Physics and Quantum Mechanics
- World War II and Post-War Activities
- Amorphous Materials and Nobel Prize
- Legacy
Neville Francis Mott: A Renowned Physicist
Early Life and EducationNeville Francis Mott, an English physicist, was born in Leeds, England, to Lilian Mary Reynolds and Charles Francis Mott. His parents met while studying physics under J.J. Thomson at the Cavendish Laboratory in Cambridge. After graduating from Clifton College in Bristol, Mott proceeded to St. John's College, Cambridge, where he pursued mathematics and theoretical physics, obtaining a bachelor's degree in 1927.
Doctoral Studies and Academic Career
Mott's doctoral research coincided with significant advancements in theoretical physics, particularly the formulation of quantum mechanics by Werner Heisenberg and Erwin Schrödinger. His research took him to Cambridge under R. Fowler, Copenhagen under Niels Bohr, and Göttingen under Max Born. Upon returning to England in 1929, he lectured at Manchester University before joining Gonville and Caius College, Cambridge, in 1930, where he received his Master's degree.
At Cambridge, Mott collaborated with Ernest Rutherford, applying quantum mechanics to particle scattering analysis. Notably, he successfully derived Rutherford's empirical formula for the scattering of alpha particles by atomic nuclei. His calculations revealed a doubling of the reaction intensity at certain scattering angles, a phenomenon later confirmed experimentally. In 1933, at the age of 28, Mott became Professor of Theoretical Physics at the University of Bristol. Along with H. Massey, he co-authored the book "The Theory of Atomic Collisions" that same year.
Solid State Physics and Quantum Mechanics
Mott's research interests diversified into various phenomena within solid state physics, especially the structural properties of metals. He developed a theory of transition metals, classifying their electrons into two groups: one primarily responsible for electrical conduction and the other for magnetism and scattering. His other investigations delved into the quenching of metallic alloys, the rectification of alternating current, the structure of ionic crystals, and photographic processes.
By the 1930s, quantum mechanics had enabled the explanation of metallic and non-metallic differences through the band theory. However, Mott's attention was drawn to an apparent contradiction: nickel oxide, theoretically expected to be metallic, was an insulator. Revisiting band theory by incorporating electron-electron interactions, Mott elucidated the properties of nickel oxide in 1949 and established why certain materials transition from insulators to conductors as electron density changes. These transitions, now known as Mott transitions, became pivotal in the development of semiconductors.
World War II and Post-War Activities
During World War II, Mott engaged in operational research, the mathematics of decision-making for strategic planning, and calculations on the range of German V-2 rockets. After the war, he resumed his position in Bristol, becoming Director of the Department of Physics in 1948. In 1954, he succeeded W.L. Bragg as the Director of the Cavendish Laboratory at Cambridge.
Amorphous Materials and Nobel Prize
In the early 1960s, Mott's research shifted to explore the electrical properties of amorphous (non-crystalline) materials, where the molecular arrangement lacks order. Triggered by Philip W. Anderson's 1958 article on amorphous semiconductors, Mott recruited Anderson as a Visiting Professor at Cambridge. From 1967 to 1975, they collaborated on understanding the electrical conductivity of semiconductors.
Anderson had demonstrated that under certain conditions, electrons lose their ability to diffuse freely in disordered solids, an effect known as Anderson localization. Initially overlooked, Mott developed Anderson's ideas, explaining numerous behaviors of electrons in amorphous materials. His concept of a mobility edge defined a critical energy level separating mobile and localized electrons. He also accounted for electrical conductivity due to the presence of relatively few foreign atoms and the minimum conductivity below which no electric current can flow or only a very small current can flow in the disordered material. This work paved the way for the use of semiconductors in solar cells, photocopiers, and countless devices.
After relinquishing his administrative duties upon retiring from Cambridge in 1971, "Mott worked on amorphous materials like a dog with two tails," according to Brian Pippard, his successor as Cavendish Director. In 1977, Mott shared the Nobel Prize in Physics with Anderson and John H. Van Vleck for "fundamental theoretical investigations into the electronic structure of magnetic and disordered systems." As Per-Olov Löwdin, a member of the Royal Swedish Academy of Sciences, stated during the presentation, "The theory of Mott and Mott-Anderson transitions... has today an important role both in the understanding of certain materials and in the development of new ones. As Anderson and Mott have shown, properly controlled disorder can be technically as important as the utmost order."
Legacy
Beyond his scientific contributions, Mott authored several articles on science education and served on educational reform committees. He chaired the board of Taylor & Francis, a scientific book publisher, from 1969 to 1977 and was Master of Gonville and Caius College, Cambridge, from 1959 to 1966. In 1930, Mott married Ruth Eleanor Horder; they had two daughters. His hobbies included religious history, photography, and collecting colored glass and Byzantine coins.
Mott received numerous honors and held honorary degrees from Oxford, London, Paris, and several other universities. The French government awarded him the Légion d'Honneur in 1977. In 1962, he was knighted.
