Leonard Mandel (May 9, 1927 – February 9, 2001) was the Lee DuBridge Professor Emeritus of Physics and Optics at the University of Rochester when he died at the age of 73 at his home in Pittsford, New York. He contributed immensely to theoretical and experimental optics. With Emil Wolf he published the highly regarded book Optical Coherence and Quantum Optics.
As written by Jeff Kimble and Emil Wolf in Physics Today; "Mandel is widely credited as being one of the founding fathers of the field of quantum optics. Although he made seminal contributions across most of quantum optics, the central theme of his research was the exploration of the nature of light through insightful theoretical analyses and a set of pioneering experiments that have become landmarks in the field. Not since the beginning of quantum mechanics has an individual so intimately investigated and so dramatically advanced our understanding of the quantum aspects of light." The reader is urged to read a more detailed description of Mandel's work in the full Physics Today obituary at the link referenced below.
Mandel was born in Berlin, Germany, where his father, Robert (Naftali) Mandel, had emigrated from Eastern Europe. He received a BSc degree in mathematics and physics in 1947 and a PhD degree in nuclear physics in 1951 from Birkbeck College, University of London, in the United Kingdom. He became a technical officer at Imperial Chemical Industries Ltd in Welwyn, UK, in 1951. In 1955, he became a lecturer and, later, senior lecturer at Imperial College London, University of London. He remained at Imperial until 1964, when he joined the University of Rochester as a professor of physics. Mandel published over 260 scientific papers dealing with problems of optical coherence, lasers, quantum interactions and non-classical states of light. Together with Prof. Emil Wolf, Mandel organized a series of international conferences, known as the Rochester Conferences on Coherence and Quantum Optics, which were extremely influential in the history of the field of Quantum Optics. Mandel was a referee for approximately 24 scientific journals and 6 research agencies. He was on the Board of Directors of the Optical Society of America from 1985-1988, and was Associate Editor of the Journal of the Optical Society 1970-1976 and 1982-1983. Mandel was also a member of the Editorial Board for both Physical Review and Quantum Optics. In addition to his ground-breaking research, Mandel was known as an exceptional teacher and in 1992 he was awarded the Faculty Graduate Teaching Award by the University of Rochester.
Mandel was a Fellow of the Optical Society of America and of the American Physical Society and received the following awards:
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference. It contains several distinct concepts, which are limiting cases that never quite occur in reality but allow an understanding of the physics of waves, and has become a very important concept in quantum physics. More generally, coherence describes all properties of the correlation between physical quantities of a single wave, or between several waves or wave packets.
Interference is the addition, in the mathematical sense, of wave functions. A single wave can interfere with itself, but this is still an addition of two waves (see Young's slits experiment). Constructive or destructive interferences are limit cases, and two waves always interfere, even if the result of the addition is complicated or not remarkable.
When interfering, two waves can add together to create a wave of greater amplitude than either one (constructive interference) or subtract from each other to create a wave of lesser amplitude than either one (destructive interference), depending on their relative phase. Two waves are said to be coherent if they have a constant relative phase. The amount of coherence can readily be measured by the interference visibility, which looks at the size of the interference fringes relative to the input waves (as the phase offset is varied); a precise mathematical definition of the degree of coherence is given by means of correlation functions.
Spatial coherence describes the correlation (or predictable relationship) between waves at different points in space, either lateral or longitudinal. Temporal coherence describes the correlation between waves observed at different moments in time. Both are observed in the Michelson–Morley experiment and Young's interference experiment. Once the fringes are obtained in the Michelson interferometer, when one of the mirrors is moved away gradually, the time for the beam to travel increases and the fringes become dull and finally disappear, showing temporal coherence. Similarly, if in a double-slit experiment, the space between the two slits is increased, the coherence dies gradually and finally the fringes disappear, showing spatial coherence. In both cases, the fringe amplitude slowly disappears, as the path difference increases past the coherence length.Emil Wolf
Emil Wolf (July 30, 1922 – June 2, 2018) was a Czech-born American physicist who made advancements in physical optics, including diffraction, coherence properties of optical fields, spectroscopy of partially coherent radiation, and the theory of direct scattering and inverse scattering. He was also the author of numerous other contributions to optics.Frederic Ives Medal
The Frederic Ives Medal is the highest award of the Optical Society, recognizing overall distinction in optics. The prize was established in 1928 by Herbert E. Ives in honor of his father, Frederic Ives. Initially awarded every two years, it has been awarded annually since 1951. The prize is funded by the Jarus W. Quinn Ives Medal Endowment.H. Jeff Kimble
H. Jeff Kimble (born April 23, 1949), is the William L. Valentine Professor and Professor of Physics at Caltech. His research is in quantum optics and is noted for groundbreaking experiments in physics including one of the first demonstrations of teleportation of a quantum state (first demonstration is disputed with Anton Zeilinger), quantum logic gate, and the development of the first single atom laser. According to Elizabeth Rogan, OSA CEO, "Jeff has led a revolution in modern physics through his pioneering research in the coherent control of the interactions of light and matter." Kimble's main research focus is in quantum information science and the quantum dynamics of open systems.Kimble graduated summa cum laude from Abilene Christian University in 1971 and earned his master's and doctoral degrees from University of Rochester, culminating in 1979. He was advised by Leonard Mandel. Along with Mandel, Kimble observed the first photon anti-bunching. He spent two years as a scientist for the General Motors Research Laboratory until 1979 when he joined the faculty at the University of Texas at Austin. He moved to the California Institute of Technology in 1989.Kimble is a Fellow of the American Association for the Advancement of Science, the American Physical Society, and the Optical Society of America, and is a member of the National Academy of Sciences.Hanbury Brown and Twiss effect
In physics, the Hanbury Brown and Twiss (HBT) effect is any of a variety of correlation and anti-correlation effects in the intensities received by two detectors from a beam of particles. HBT effects can generally be attributed to the wave–particle duality of the beam, and the results of a given experiment depend on whether the beam is composed of fermions or bosons. Devices which use the effect are commonly called intensity interferometers and were originally used in astronomy, although they are also heavily used in the field of quantum optics.Hong–Ou–Mandel effect
The Hong–Ou–Mandel effect is a two-photon interference effect in quantum optics which was demonstrated in 1987 by three physicists from the University of Rochester: Chung Ki Hong, Zhe Yu Ou and Leonard Mandel. The effect occurs when two identical single-photon waves enter a 1:1 beam splitter, one in each input port. When the photons are identical, they will extinguish each other. If they become more distinguishable, the probability of detection will increase. In this way the interferometer can accurately measure bandwidth, path lengths and timing.Index of physics articles (L)
The index of physics articles is split into multiple pages due to its size.
To navigate by individual letter use the table of contents below.List of Birkbeck, University of London people
A list of Birkbeck, University of London people, including alumni, members of faculty and fellows.List of Imperial College London people
This is a list of Imperial College London people, including notable students and staff from the various historical institutions which are now part of Imperial College.
Students who later became academics at Imperial are listed in the alumni section only to avoid duplication.Mandel
Mandel is a surname that occurs in multiple cultures and languages. It is a Dutch, German and Jewish surname, meaning "almond", from the Middle High German and Middle Dutch mandel. Mandel can be a locational surname, from places called Mandel, such as Mandel, Germany. Mandel may also be a Dutch surname, from the Middle Dutch mandele, meaning a number of sheaves of harvested wheat.Notable people with the surname include:
Alon Mandel (born 1988), Israeli swimmer
Babaloo Mandel (born 1949), American screenwriter
David Mandel (born 1970), American television producer and writer
Eli Mandel (1922–1992), Canadian writer
Emily St. John Mandel (born 1979), Canadian novelist
Emmanuil Mandel (born 1925), Russian poet
Ernest Mandel (1923–1995), Belgian politician, professor and writer.
Georges Mandel (1885–1944), French politician
Harvey Mandel (born 1945), American guitarist
Howie Mandel (born 1955), Canadian actor and comedian
Jan Mandel (born 1956), American mathematician
Jean Mandel (1911–1974), German footballer and politician
Jeanne Dorsey Mandel (1937–2001), American public official and Maryland first lady
Jennifer R. Mandel, American biologist
Johnny Mandel (born 1925), American musician
Josh Mandel (born 1977), American politician
Julius Mandel (also known as Gyula Mándi (1899–1969), Hungarian Olympic footballer and manager
Leonard Mandel (1927–2001), American physicist
Loring Mandel (born 1928), American playwright
Maria Mandel (1912–1948), Austrian Nazi official
Marvin Mandel (1920–2015) American politician
Morton Mandel (born 1921), American businessman
Robert Mandel (born 1945), American film producer
Rolfe D. Mandel (born 1952), American archaeologist
Sammy Mandel (1904–1967), American boxer
Semyon Mandel (1907–1974), Russian theatre and film designer
Seth Mandel (born 1982), American conservative writer and editor
Stephen Mandel (born 1945), Canadian politician
Stephen Mandel (hedge fund manager) (born 1956), American businessman
Stewart Mandel (born 1976), American sportswriter
Suzy Mandel (born 1953), British actress
Tom Mandel (futurist) (1946–1995), American futurist
Tom Mandel (poet) (born 1942), American poet
William Mandel (1917–2016), American journalist
Will Mandel (born 2000), American hacky sackerMax Born Award
The Max Born Award is given by the Optical Society (formerly the Optical Society of America) for "outstanding contributions to physical optics", and is named after Max Born.OSA Fellow
The OSA Fellow is a membership designation of The Optical Society (OSA) that denotes distinguished scientific accomplishment. The bylaws of this society only allow 10% of its membership to be designated as an OSA Fellow. The OSA Fellow requires peer group nomination.Quantum optics
Quantum optics (QO) is a field of research that uses semi-classical and quantum-mechanical physics to investigate phenomena involving light and its interactions with matter at submicroscopic levels. In other words it is quantum mechanics applied to photons or light.Rupamanjari Ghosh
Rupamanjari Ghosh is the present Vice-Chancellor of Shiv Nadar University, Uttar Pradesh, India. She is also the former Director of School of Natural Sciences and Dean of Research & Graduate Studies at Shiv Nadar University, and a Professor of physics and former Dean at the School of Physical Sciences, Jawaharlal Nehru University, New Delhi. Her areas of interest include Experimental and Theoretical Quantum Optics, Laser Physics, Nonlinear Optics, Quantum Information, Quantum Measurement and Magneto-Optics.Shot noise
Shot noise or Poisson noise is a type of noise which can be modeled by a Poisson process.
In electronics shot noise originates from the discrete nature of electric charge. Shot noise also occurs in photon counting in optical devices, where shot noise is associated with the particle nature of light.Spontaneous parametric down-conversion
Spontaneous parametric down-conversion (also known as SPDC, parametric fluorescence or parametric scattering) is a nonlinear instant optical process that converts one photon of higher energy (namely, a pump photon), into a pair of photons (namely, a signal photon, and an idler photon) of lower energy, in accordance with the law of conservation of energy and law of conservation of momentum. It is an important process in quantum optics, for the generation of entangled photon pairs, and of single photons.Stochastic electrodynamics
Stochastic electrodynamics (SED) is an extension of the de Broglie–Bohm interpretation of quantum mechanics, with the electromagnetic zero-point field (ZPF) playing a central role as the guiding pilot-wave. The theory is a deterministic nonlocal hidden-variable theory. It is distinct from other more mainstream interpretations of quantum mechanics such as QED, a stochastic electrodynamics of the Copenhagen interpretation and Everett's many-worlds interpretation. SED describes energy contained in the electromagnetic vacuum at absolute zero as a stochastic, fluctuating zero-point field. The motion of a particle immersed in this stochastic zero-point radiation generally results in highly nonlinear, sometimes chaotic or emergent, behaviour. Modern approaches to SED consider the quantum properties of waves and particles as well-coordinated emergent effects resulting from deeper (sub-quantum) nonlinear matter-field interactions.Given the posited emergent nature of quantum laws in SED, it has been argued that they form a kind of "quantum equilibrium" that has an analogous status to that of thermal equilibrium in classical dynamics. In principle therefore, SED allows other "quantum non-equilibrium" distributions, for which the statistical predictions of quantum theory are violated. It is controversially argued that quantum theory is merely a special case of a much wider nonlinear physics, a physics in which non-local (superluminal) signalling is possible, and in which the uncertainty principle can be violated. It has also been proposed that inertia is one such emergent law. The reported results are subject to considerable argument, with accusations that it leads to the possibility of anti-gravity, reactionless drives or free energy.The Institute of Optics
The Institute of Optics is a department and research center at the University of Rochester in Rochester, New York. The Institute grants degrees at the bachelor's, master's and doctoral levels through the University of Rochester School of Engineering and Applied Sciences. Since its founding, the Institute has granted over 2,400 degrees in optics, making up about half of the degrees awarded in the field in the U.S. The Institute is made up of 16 full-time professors, 8 professors with joint appointments in other departments, 5 adjunct professors, 12 research scientists, 11 staff, about 100 undergraduate students and about 100 graduate students.According to the National Research Council, in its latest ranking of physics departments, the Institute of Optics was ranked 25th in the nation.Thomas Young Medal and Prize
The Thomas Young Medal and Prize is a prize awarded on odd numbered years by the Institute of Physics in the memory of Thomas Young for distinguished research in the field of optics, including physics outside the visible region. Originally established by the Optical Society in 1907 as the Thomas Young Oration 'on an optical subject', the orator was later chosen by the Physical Society after the two societies had merged in 1932 and subsequently converted to a medal and prize after the Physical Society had in turn merged with the Institute of Physics in 1960.