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Fermionic Condensate
A fermionic condensate or Fermi–Dirac condensate is a superfluid phase formed by fermionic particles at low temperatures. It is closely related to the Bose–Einstein condensate, a superfluid phase formed by bosonic atoms under similar conditions. The earliest recognized fermionic condensate described the state of electrons in a superconductor; the physics of other examples including recent work with fermionic atoms is analogous. The first atomic fermionic condensate was created by a team led by Deborah S. Jin using potassium-40 atoms at the University of Colorado Boulder in 2003. Background Superfluidity Fermionic condensates are attained at lower temperatures than Bose–Einstein condensates. Fermionic condensates are a type of superfluid. As the name suggests, a superfluid possesses fluid properties similar to those possessed by ordinary liquids and gases, such as the lack of a definite shape and the ability to flow in response to applied forces. However, superfluids pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superfluid
Superfluidity is the characteristic property of a fluid with zero viscosity which therefore flows without any loss of kinetic energy. When stirred, a superfluid forms vortices that continue to rotate indefinitely. Superfluidity occurs in two isotopes of helium (helium-3 and helium-4) when they are liquefied by cooling to cryogenic temperatures. It is also a property of various other exotic states of matter theorized to exist in astrophysics, high-energy physics, and theories of quantum gravity. The theory of superfluidity was developed by Soviet theoretical physicists Lev Landau and Isaak Khalatnikov. Superfluidity is often coincidental with Bose–Einstein condensation, but neither phenomenon is directly related to the other; not all Bose–Einstein condensates can be regarded as superfluids, and not all superfluids are Bose–Einstein condensates. Superfluidity of liquid helium Superfluidity was discovered in helium-4 by Pyotr Kapitsa and independently by John F. Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum State
In quantum physics, a quantum state is a mathematical entity that provides a probability distribution for the outcomes of each possible measurement on a system. Knowledge of the quantum state together with the rules for the system's evolution in time exhausts all that can be predicted about the system's behavior. A mixture of quantum states is again a quantum state. Quantum states that cannot be written as a mixture of other states are called pure quantum states, while all other states are called mixed quantum states. A pure quantum state can be represented by a ray in a Hilbert space over the complex numbers, while mixed states are represented by density matrices, which are positive semidefinite operators that act on Hilbert spaces. Pure states are also known as state vectors or wave functions, the latter term applying particularly when they are represented as functions of position or momentum. For example, when dealing with the energy spectrum of the electron in a hydrogen at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rudolf Grimm
Rudolf Grimm (born 10 November 1961) is an experimental physicist from Austria. His work centres on ultracold atoms and quantum gases. He was the first scientist worldwide who, with his team, succeeded in realizing a Bose–Einstein condensation of molecules. Career Grimm graduated in physics from the University of Hannover in 1986. From 1986 to 1989 he was a post-graduate researcher at the ETH Zurich (Swiss Federal Institute of Technology), then went on to the Institute of Spectroscopy of the USSR Academy of Sciences in Troitsk near Moscow for half a year. He spent the next ten years in Heidelberg as a researcher at the Max Planck Institute for Nuclear Physics. In 1994, Grimm applied to the University of Heidelberg to qualify as a professor by receiving the "venia docendi" in experimental physics. In the year 2000, he was appointed to a chair in experimental physics at the University of Innsbruck, where he has been Dean of the Faculty for Mathematics, Computer Science and Phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to the magnetic field. A permanent magnet's magnetic field pulls on ferromagnetic materials such as iron, and attracts or repels other magnets. In addition, a nonuniform magnetic field exerts minuscule forces on "nonmagnetic" materials by three other magnetic effects: paramagnetism, diamagnetism, and antiferromagnetism, although these forces are usually so small they can only be detected by laboratory equipment. Magnetic fields surround magnetized materials, and are created by electric currents such as those used in electromagnets, and by electric fields varying in time. Since both strength and direction of a magnetic field may vary with location, it is described mathematically by a function assigning a vector to each point of space, cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JILA
JILA, formerly known as the Joint Institute for Laboratory Astrophysics, is a physical science research institute in the United States. JILA is located on the University of Colorado Boulder campus. JILA was founded in 1962 as a joint institute of The University of Colorado Boulder and the National Institute of Standards & Technology. Research JILA is one of the nation’s leading research institutes in the physical sciences. The world's first Bose-Einstein Condensate was created at JILA by Eric Cornell and Carl Wieman in 1995. The first frequency comb demonstration was led by John L. Hall at JILA. The first demonstrations of a Fermionic condensate and BEC-BCS crossover physics were done by Deborah S. Jin. JILA's members hold faculty appointments in the Departments of Physics; Astrophysical and Planetary Science; Chemistry and Biochemistry; and Molecular, Cellular, and Developmental Biology as well as Engineering. JILA’s Quantum Physics Division of NIST members hold joint facu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Wieman
Carl Edwin Wieman (born March 26, 1951) is an American physicist and educationist at Stanford University, and currently the A.D White Professor at Large at Cornell University. In 1995, while at the University of Colorado Boulder, he and Eric Allin Cornell produced the first true Bose–Einstein condensate (BEC) and, in 2001, they and Wolfgang Ketterle (for further BEC studies) were awarded the Nobel Prize in Physics. Wieman currently holds a joint appointment as Professor of Physics and Professor in the Stanford Graduate School of Education, as well as the DRC Professor in the Stanford University School of Engineering. In 2020, Wieman was awarded the Yidan Prize in Education Research for "his contribution in developing new techniques and tools in STEM education.citation Biography Wieman was born in Corvallis, Oregon to N. Orr Wieman and Alison Marjorie Fry in the United States and graduated from Corvallis High School. His paternal grandfather Henry Nelson Wieman was a religi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eric Cornell
Eric Allin Cornell (born December 19, 1961) is an American physicist who, along with Carl E. Wieman, was able to synthesize the first Bose–Einstein condensate in 1995. For their efforts, Cornell, Wieman, and Wolfgang Ketterle shared the Nobel Prize in Physics in 2001. Biography Cornell was born in Palo Alto, California, where his parents were completing graduate degrees at nearby Stanford University. Two years later he moved to Cambridge, Massachusetts, where his father was a professor of civil engineering at MIT. Here he grew up with his younger brother and sister, with yearlong intermezzos in Berkeley, California, and Lisbon, Portugal, where his father spent sabbatical years. In Cambridge he attended Cambridge Rindge and Latin, Cambridge Rindge and Latin School. The year before his graduation he moved back to California with his mother and finished high school at San Francisco's Lowell High School (San Francisco), Lowell High School, a local magnet school for academically ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas D
Douglas may refer to: People * Douglas (given name) * Douglas (surname) Animals *Douglas (parrot), macaw that starred as the parrot ''Rosalinda'' in Pippi Longstocking *Douglas the camel, a camel in the Confederate Army in the American Civil War Businesses * Douglas Aircraft Company * Douglas (cosmetics), German cosmetics retail chain in Europe * Douglas (motorcycles), British motorcycle manufacturer Peerage and Baronetage * Duke of Douglas * Earl of Douglas, or any holder of the title * Marquess of Douglas, or any holder of the title * Douglas Baronets Peoples * Clan Douglas, a Scottish kindred * Dougla people, West Indians of both African and East Indian heritage Places Australia * Douglas, Queensland, a suburb of Townsville * Douglas, Queensland (Toowoomba Region), a locality * Port Douglas, North Queensland, Australia * Shire of Douglas, in northern Queensland Belize * Douglas, Belize Canada * Douglas, New Brunswick * Douglas Parish, New Brunswick * Douglas, O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helium-3
Helium-3 (3He see also helion) is a light, stable isotope of helium with two protons and one neutron (the most common isotope, helium-4, having two protons and two neutrons in contrast). Other than protium (ordinary hydrogen), helium-3 is the only stable isotope of any element with more protons than neutrons. Helium-3 was discovered in 1939. Helium-3 occurs as a primordial nuclide, escaping from Earth's crust into its atmosphere and into outer space over millions of years. Helium-3 is also thought to be a natural nucleogenic and cosmogenic nuclide, one produced when lithium is bombarded by natural neutrons, which can be released by spontaneous fission and by nuclear reactions with cosmic rays. Some of the helium-3 found in the terrestrial atmosphere is also an artifact of atmospheric and underwater nuclear weapons testing. Much speculation has been made over the possibility of helium-3 as a future energy source. Unlike most nuclear fusion reactions, the fusion of helium-3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooper Pair
In condensed matter physics, a Cooper pair or BCS pair (Bardeen–Cooper–Schrieffer pair) is a pair of electrons (or other fermions) bound together at low temperatures in a certain manner first described in 1956 by American physicist Leon Cooper. Cooper pair Cooper showed that an arbitrarily small attraction between electrons in a metal can cause a paired state of electrons to have a lower energy than the Fermi energy, which implies that the pair is bound. In conventional superconductors, this attraction is due to the electron–phonon interaction. The Cooper pair state is responsible for superconductivity, as described in the BCS theory developed by John Bardeen, Leon Cooper, and John Schrieffer for which they shared the 1972 Nobel Prize. Although Cooper pairing is a quantum effect, the reason for the pairing can be seen from a simplified classical explanation. An electron in a metal normally behaves as a free particle. The electron is repelled from other electrons due to thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Robert Schrieffer
John Robert Schrieffer (; May 31, 1931 – July 27, 2019) was an American physicist who, with John Bardeen and Leon Cooper, was a recipient of the 1972 Nobel Prize in Physics for developing the BCS theory, the first successful quantum theory of superconductivity. Life and career Schrieffer was born in Oak Park, Illinois, the son of Louise (Anderson) and John Henry Schrieffer. His family moved in 1940 to Manhasset, New York, and then in 1947 to Eustis, Florida, where his father, a former pharmaceutical salesman, began a career in the citrus industry. In his Florida days, Schrieffer enjoyed playing with homemade rockets and ham radio, a hobby that sparked an interest in electrical engineering. After graduating from Eustis High School in 1949, Schrieffer was admitted to the Massachusetts Institute of Technology, where for two years he majored in electrical engineering before switching to physics in his junior year. He completed a bachelor's thesis on multiplets in heavy at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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