Sir Nevill Francis Mott (30 September 1905 – 8 August 1996) was a British
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate caus ...
who won the
Nobel Prize for Physics in 1977 for his work on the electronic structure of magnetic and
disordered systems, especially
amorphous semiconductors. The award was shared with
Philip W. Anderson and
J. H. Van Vleck. The three had conducted loosely related research. Mott and Anderson clarified the reasons why magnetic or amorphous materials can sometimes be metallic and sometimes insulating.
Education and early life
Mott was born in
Leeds to Lilian Mary Reynolds and
Charles Francis Mott and grew up first in the village of
Giggleswick, in the
West Riding of Yorkshire, where his father was Senior Science Master at
Giggleswick School. His mother also taught Maths at the School. The family moved (due to his father's jobs) first to Staffordshire, then to Chester and finally Liverpool, where his father had been appointed Director of Education. Mott was at first educated at home by his mother, who was a Cambridge Mathematics Tripos graduate. His parents had met in the
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the School of Physical Sciences. The laboratory was opened in 1874 on the New Museums Site as a laboratory for experimental physics and is named ...
, when both were engaged in physics research. At age ten, he began formal education at
Clifton College
''The spirit nourishes within''
, established = 160 years ago
, closed =
, type = Public schoolIndependent boarding and day school
, religion = Christian
, president =
, head_label = Head of College
, hea ...
in Bristol, followed by study at
St John's College, Cambridge, where he read the
Mathematics Tripos
The Mathematical Tripos is the mathematics course that is taught in the Faculty of Mathematics at the University of Cambridge. It is the oldest Tripos examined at the University.
Origin
In its classical nineteenth-century form, the tripos was a ...
.
Career and research
Mott was appointed a Lecturer in the
Physics Department at the
University of Manchester in 1929. He returned to Cambridge in 1930 as a Fellow and lecturer of
Gonville and Caius College
Gonville and Caius College, often referred to simply as Caius ( ), is a constituent college of the University of Cambridge in Cambridge, England. Founded in 1348, it is the fourth-oldest of the University of Cambridge's 31 colleges and one of t ...
, and in 1933 moved to the
University of Bristol
The University of Bristol is a Red brick university, red brick Russell Group research university in Bristol, England. It received its royal charter in 1909, although it can trace its roots to a Society of Merchant Venturers, Merchant Venturers' sc ...
as Melville Wills Professor in Theoretical Physics.
In 1948 he became
Henry Overton Wills Professor of Physics and Director of the
Henry Herbert Wills
Henry Herbert 'Harry' Wills (20 March 1856 – 11 May 1922) was a businessman and philanthropist from Bristol, and a member of the Wills tobacco family.
He was the son of Henry Overton Wills III and Alice Hopkinson and was born in Clifton, Bris ...
Physical Laboratory at Bristol. In 1954 he was appointed
Cavendish Professor of Physics The Cavendish Professorship is one of the senior faculty positions in physics at the University of Cambridge. It was founded on 9 February 1871 alongside the famous Cavendish Laboratory, which was completed three years later. William Cavendish, 7th ...
at Cambridge, a post he held until 1971. He was instrumental in the painful cancellation of the planned
particle accelerator
A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies, and to contain them in well-defined beams.
Large accelerators are used for fundamental research in particle ...
because of its very high cost. He also served as Master of
Gonville and Caius College
Gonville and Caius College, often referred to simply as Caius ( ), is a constituent college of the University of Cambridge in Cambridge, England. Founded in 1348, it is the fourth-oldest of the University of Cambridge's 31 colleges and one of t ...
, 1959–1966.
His early works were on the theoretical analysis of collisions in gases, notably the
collision with spin flip of an electron against a hydrogen atom, which would stimulate subsequent works by André Blandin and
Jun Kondo
Jun or JUN may refer to:
People and anthroponymy
* Jun (given name), a common Japanese given name
* Jun (singer), a member of South Korean boy band U-KISS
* Tomáš Jun, Czech footballer
* A spelling of common Korean family name Jeon (Korean surn ...
about similar effects between
conduction electrons
In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level, and thus determine the electrical conductivity of the solid. In nonmetals, the valence band is the highest range of electron energies in w ...
, as well as magnetic properties in metals. This sort of activity led Mott to writing two books. The first one, which was edited together with
Ian Sneddon, gives a simple and clear description of quantum mechanics, with an emphasis on the
Schrödinger equation in
real space. The second describes atomic and electronic collisions in gases, using the rotational symmetry of
electronic states in the
Hartree–Fock method.
But already in the middle of the 1930s, Mott's interests had broadened to include solid states, leading to two more books that would have a great impact on the development of the field in the years prior and after
World War II. In 1936, ''Theory of the Properties of Metals and Alloys'' (written together with H. Jones) describes a simplified framework which led to rapid progress.
The concept of
nearly free valence electrons in metallic alloys explained the special stability of the
Hume-Rothery phases if the
Fermi sphere of the ''sp''
Valence electron, treated as free, would be scattered by the
Brillouin zone
In mathematics and solid state physics, the first Brillouin zone is a uniquely defined primitive cell in reciprocal space. In the same way the Bravais lattice is divided up into Wigner–Seitz cells in the real lattice, the reciprocal lattice i ...
boundaries of the atomic structure. The description of the impurities in metals by the
Thomas Fermi approximation would explain why such impurities would not interact at long range. Finally the delocalisation of the
valence ''d'' electrons in
transitional metals and alloys would explain the possibility for the
magnetic moments of atoms to be expressed as fractions of
Bohr magneton
In atomic physics, the Bohr magneton (symbol ) is a physical constant and the natural unit for expressing the magnetic moment of an electron caused by its orbital or spin angular momentum.
The Bohr magneton, in SI units is defined as
\mu_\mathrm ...
s, leading to
ferro or
antiferromagnetic
In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules, usually related to the spins of electrons, align in a regular pattern with neighboring spins (on different sublattices) pointing in opposite directions. ...
coupling at short range. This last contribution, produced at the first international conference on magnetism, held in
Strasbourg in May 1939, reinforced similar points of view defended at the time in France by the future Nobel laureate
Louis Néel. In 1949, Mott suggested to
Jacques Friedel
Jacques Friedel ForMemRS (; 11 February 1921 – 27 August 2014) was a French physicist and material scientist.
Education
Friedel attended the Cours Hattemer, a private school. He studied at the École Polytechnique from 1944 to 1946, and the É ...
to use the approach developed together with Marvey for a more accurate description of the
electric-field screening
In physics, screening is the damping of electric fields caused by the presence of mobile charge carriers. It is an important part of the behavior of charge-carrying fluids, such as ionized gases (classical plasmas), electrolytes, and charge car ...
of the impurity in a metal, leading to the characteristic long range charge oscillations. Friedel also used the concept developed in that book of virtual bound level to describe a situation when the atomic potential considered is not quite strong enough to create a (real) bound level of symmetry e ≠ o. The consequences of these remarks on the more exact approaches of cohesion in rp as well as d metals were mostly developed by his students in Orsay.
The second book, with
Ronald Wilfred Gurney
Ronald Wilfred (or Wilfrid) Gurney (1898, in Cheltenham, England – 14 April 1953, in New York, New York) was a British theoretical physicist and research pupil of William Lawrence Bragg at the Victoria University of Manchester during the 1920s ...
, ''On the Physical Chemistry of Solids'' was more wide-ranging. It treated notably of the oxidation of metals at low temperatures, where it described the growth of the oxide layer as due to the electric field developed between the metal and absorbed oxygen ions, which could force the way of metallic or oxygen ions through a disordered oxide layer. The book also analysed the photographic reactions in ionic silver compound in terms of precipitation of silver ions into metallic clusters.
This second field had a direct and long lasting consequence on the research activity of John (Jack) Mitchell. Mott's accomplishments include explaining theoretically the effect of light on a
photographic emulsion
Photographic emulsion is a light-sensitive colloid used in film-based photography. Most commonly, in silver-gelatin photography, it consists of silver halide crystals dispersed in gelatin. The emulsion is usually coated onto a substrate of glas ...
(see
latent image). His work on oxidation, besides fostering new research in the field (notably by J. Bénard and
Nicolás Cabrera
Nicolás Cabrera (1913–1989), was a Spanish physicist who did important work on the theories of crystal growth (specifically the Burton–Cabrera–Frank theory) and the oxidisation of metals. He was the son of another famous Spanish physic ...
), was the root of the concept of the
band gap
In solid-state physics, a band gap, also called an energy gap, is an energy range in a solid where no electronic states can exist. In graphs of the electronic band structure of solids, the band gap generally refers to the energy difference (i ...
produced in semiconductors by gradients in the distribution of
donor and acceptor impurities.
During the war Mott worked on the role of plastic deformation in the progression of fracture cracks. When he returned to Bristol after the war, his having met and hired
Frederick Charles Frank enabled the two of them to make considerable advances in the study of
dislocations
In materials science, a dislocation or Taylor's dislocation is a linear crystallographic defect or irregularity within a crystal structure that contains an abrupt change in the arrangement of atoms. The movement of dislocations allow atoms to s ...
, with the help of others such as
Frank Nabarro
Frank Reginald Nunes Nabarro MBE OMS FRS (7 March 1916 – 20 July 2006) was an English-born South African physicist and one of the pioneers of solid-state physics, which underpins much of 21st-century technology.
Education
Born 7 March 191 ...
and
Alan Cottrell
Sir Alan Howard Cottrell, FRS (17 July 1919 – 15 February 2012) was an English metallurgist and physicist. He was also former Chief Scientific Advisor to the UK Government and vice-chancellor of Cambridge University 1977–1979.
Early ...
. Bristol became an important centre of research in this topic, especially at the end of the 1940s. If Mott only produced early and somewhat minor contributions to that field, notably on alloy hardening with Nabarro and on the topology of a dislocation network lowering the apparent elastic constants of a crystal, there is no doubt that Mott's enthusiasm played its role in the three major steps forward in the field by F. C. Frank on crystal growth and plasticity and later, in Cambridge, by P. Hirsch on thin film
electron microscopy
An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a hi ...
.
At the same time, however, Mott gave a lot of thought to
electronic correlations and their possible role in
Verwey's compounds such as nickel oxides which could switch from metals to nonmetallic insulators under various physical conditions - this is known as the
Mott transition A Mott transition is a metal-nonmetal transition in condensed matter. Due to electric field screening the potential energy becomes much more sharply (exponentially) peaked around the equilibrium position of the atom and electrons become localized an ...
. The term
Mott insulator
Mott insulators are a class of materials that are expected to conduct electricity according to conventional band theories, but turn out to be insulators (particularly at low temperatures). These insulators fail to be correctly described by band ...
is also named for him, as well as the
Mott polynomials In mathematics the Mott polynomials ''s'n''(''x'') are polynomials introduced by who applied them to a problem in the theory of electrons.
They are given by the exponential generating function
: e^=\sum_n s_n(x) t^n/n!.
Because the factor in t ...
, which he introduced.
Publications
N. F. Mott revived the old
Philosophical Magazine
The ''Philosophical Magazine'' is one of the oldest scientific journals published in English. It was established by Alexander Tilloch in 1798;John Burnett"Tilloch, Alexander (1759–1825)" Oxford Dictionary of National Biography, Oxford Unive ...
and transformed it into a lively publication essentially centred on the then-new field of solid state physics, attracting writers, readers and general interest on a wide scale. After receiving a paper on point defects in crystals by
Frederick Seitz
Frederick Seitz (July 4, 1911 – March 2, 2008) was an American physicist and a pioneer of solid state physics and lobbyist.
Seitz was the 4th president of Rockefeller University from 1968–1978, and the 17th president of the United States Nat ...
that was obviously too long for the journal, Mott decided to create a new publication,
Advances in Physics
''Advances in Physics'' is a bimonthly scientific journal published by Taylor & Francis that was established in 1952. The journal is also issued as a supplement to the ''Philosophical Magazine''. Peer review is determined on a case-by-case basis. ...
, for such review papers. Both publications are still active in 2017.
* N. F. Mott, "The Wave Mechanics of α-Ray Tracks", Proceedings of the Royal Society (1929) A126, pp. 79–84, . (reprinted as Sec. I-6 of ''Quantum Theory and Measurement'', J. A. Wheeler. and W. H. Zurek, (1983) Princeton).
* N. F. Mott, ''Metal-Insulator Transitions'', second edition (Taylor & Francis, London, 1990). ,
* N. F. Mott, ''A Life in Science'' (Taylor & Francis, London, 1986). ,
* N. F. Mott, H. Jones, ''The Theory of Properties of Metals and Alloys'', (Dover Publications Inc., New York, 1958)
*
Brian Pippard
Sir Alfred Brian Pippard, FRS (7 September 1920 – 21 September 2008), was a British physicist. He was Cavendish Professor of Physics from 1971 until 1982 and an Honorary Fellow of Clare Hall, Cambridge, of which he was the first President.
...
, ''Nevill Francis Mott'',
Physics Today, March 1997, pp. 95 and 96
(pdf)
Awards and honours
In 1977, Nevill Mott was awarded the
Nobel Prize in Physics
)
, image = Nobel Prize.png
, alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...
, together with
Philip Warren Anderson and
John Hasbrouck Van Vleck "for their fundamental theoretical investigations of the electronic structure of magnetic and disordered systems." The news of having won the Nobel Prize received Mott while having lunch at restaurant ''Die Sonne'' in
Marburg, Germany, during a visit to fellow solid state scientist at
Marburg University
The Philipps University of Marburg (german: Philipps-Universität Marburg) was founded in 1527 by Philip I, Landgrave of Hesse, which makes it one of Germany's oldest universities and the oldest still operating Protestant university in the wo ...
.
Mott was elected a
Fellow of the Royal Society (FRS) in 1936.
Mott served as president of the
Physical Society in 1957. In the early 1960s he was chairman of the British
Pugwash group. He was knighted in 1962.
Mott received an honorary Doctorate from
Heriot-Watt University
Heriot-Watt University ( gd, Oilthigh Heriot-Watt) is a public research university based in Edinburgh, Scotland. It was established in 1821 as the School of Arts of Edinburgh, the world's first mechanics' institute, and subsequently granted univ ...
in 1972.
In 1981, Mott became a founding member of the
World Cultural Council
The World Cultural Council is an international organization whose goals are to promote cultural values, goodwill and philanthropy among individuals. The organization founded in 1981 and based in Mexico, has held a yearly award ceremony since 198 ...
.
He continued to work until he was about ninety. He was made a
Companion of Honour
The Order of the Companions of Honour is an order of the Commonwealth realms. It was founded on 4 June 1917 by King George V as a reward for outstanding achievements. Founded on the same date as the Order of the British Empire, it is sometime ...
in 1995.
In 1995, Mott visited the
Loughborough University Department of Physics and presented a lecture entitled "65 Years in Physics". The University continues to host the annual Sir Nevill Mott Lecture.
Personal life
Mott was married to Ruth Eleanor Horder, and had two daughters, Elizabeth and Alice. He died in
Milton Keynes
Milton Keynes ( ) is a city and the largest settlement in Buckinghamshire, England, about north-west of London. At the 2021 Census, the population of its urban area was over . The River Great Ouse forms its northern boundary; a tributary, ...
, Buckinghamshire. His autobiography, ''A Life in Science'', was published in 1986 by Taylor & Francis.
A Life In Science
Mott died on 8 August, 1996 at the age 90.
References
External links
*
*
* including the Nobel Lecture, 8 December 1977 ''Electrons in Glass''
{{DEFAULTSORT:Mott, Nevill Francis
1905 births
1996 deaths
Alumni of St John's College, Cambridge
Academics of the University of Bristol
English physicists
British Nobel laureates
Fellows of Gonville and Caius College, Cambridge
Masters of Gonville and Caius College, Cambridge
Fellows of the Royal Society
Foreign associates of the National Academy of Sciences
Members of the Order of the Companions of Honour
Nobel laureates in Physics
People educated at Clifton College
People educated at Giggleswick School
Royal Medal winners
Recipients of the Copley Medal
Knights Bachelor
Presidents of the Physical Society
English Nobel laureates
Founding members of the World Cultural Council
20th-century British physicists
Scientists from Yorkshire
Cavendish Professors of Physics
Presidents of the International Union of Pure and Applied Physics