Brian Kidd Ridley (2 March 1931 – 22 May 2024) was a British solid-state physicist specialising in semiconductor theory. He was an emeritus professor at the University of Essex.
Early life and education
Ridley was born on 2 March 1931.
He educated at the University of Durham.
He received a BSc degree in physics in 1953 and completed his doctoral studies in 1957.
Career
Ridley began his career as a research physicist in the solid-state physics division of the
Mullard Research Laboratories in Redhill, Surrey (1956–1964).
In 1964, he joined the University of Essex as a lecturer in physics, later becoming a senior lecturer (1967), reader (1971) and finally professor of physics (1984), before retiring in 2008.
He has held distinguished visiting professorial appointments at Cornell University (1967) and the Danish Technical University (1969), and has held research appointments at Princeton, Stanford, Lund, Santa Barbara, Oregon, and Eindhoven.
Research
Ridley conducted work on negative differential resistance (NDR),
instability and hot-electron transport in
. In the early 1960s,
he jointly discovered the electron transfer mechanism (Ridley–Watkins–Hilsum effect) which underlies microwave generation in
, and he was the first to discover the
impurity barrier mechanism for NDR, and to demonstrate its existence in
germanium. He was also the first to describe the consequences of NDR instabilities in terms of propagating dipole domains and
. The existence of these
nonlinearity entities has been verified in a wide variety of solids. His work on acoustoelectric instabilities led to his invention of the microsonic analogue of the
laser. He has made original contributions to the theory of electron transitions in solids, particularly impurity scattering and multiphonon processes. This work is the subject of his monograph
Quantum Processes in Semiconductors, widely used as a reference text.
He wrote three popular books, Time, Space and Things (1976), which has been translated into multiple languages, The Physical Environment (1979) and On Science (2001).
Death
Ridley died on 22 May 2024, at the age of 93.
Awards and honours
Ridley was elected a Fellow of the Royal Society (FRS) in 1994.
[ One or more of the preceding sentences may incorporate text from the royalsociety.org website where "all text published under the heading 'Biography' on Fellow profile pages is available under Creative Commons Attribution 4.0 International License." ] In 2001, the Institute of Physics awarded him the Dirac Medal in recognition of his four-decade long
influence on the semiconductor theory.
Selected works
Textbooks
Books
Research papers
External links
