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Cryotron
The cryotron is a switch that operates using superconductivity. The cryotron works on the principle that magnetic fields destroy superconductivity. This simple device consists of two superconducting wires (e.g. tantalum and niobium) with different critical temperature (''T''c). The cryotron was invented by Dudley Allen Buck of the Massachusetts Institute of Technology Lincoln Laboratory. Timeline * December 1953 The magnetically controlled switch is proposed in Dudley Allen Buck notebook. * July 1955 Dudley A. Buck application for U.S. Paten2,832,897() ''Magnetically Controlled Gating Element'' * August 1955 Lincoln LaboratorMemorandum 6M-3843'The Cryotron - A Superconductive Computer Component'' * 195A Cryotron Catalog Memory Systemby Al Slade and Howard McMahon * 1957 James W. Crowe application for U.S. paten''Superconducting Gating Devices'' Design As described by Buck, a straight wire of tantalum (having lower ''T''c) is wrapped around with a wire of niobium in a sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dudley Allen Buck
(Dr.) Dudley Allen Buck (1927–1959) was an electrical engineer and inventor of components for high-speed computing devices in the 1950s. He is best known for the invention of the cryotron, a superconductive computer component that is operated in liquid helium at a temperature near absolute zero. Other inventions were ferroelectric memory, content-addressable memory, non-destructive sensing of magnetic fields, and writing printed circuits with a beam of electrons. Early life Dudley A. Buck was born in San Francisco, California on April 25, 1927. Dudley and his siblings moved to Santa Barbara, California, in 1940. In 1943, Dudley Buck earned his amateur radio license W6WCK and a First Class Radiotelephone Operator license for commercial work. He worked part-time at Santa Barbara radio station KTMS until he left to attend college at the University of Washington under the U.S. Navy V-12 program. After graduating from the University of Washington in 1947, Buck served in the U.S. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryotron
The cryotron is a switch that operates using superconductivity. The cryotron works on the principle that magnetic fields destroy superconductivity. This simple device consists of two superconducting wires (e.g. tantalum and niobium) with different critical temperature (''T''c). The cryotron was invented by Dudley Allen Buck of the Massachusetts Institute of Technology Lincoln Laboratory. Timeline * December 1953 The magnetically controlled switch is proposed in Dudley Allen Buck notebook. * July 1955 Dudley A. Buck application for U.S. Paten2,832,897() ''Magnetically Controlled Gating Element'' * August 1955 Lincoln LaboratorMemorandum 6M-3843'The Cryotron - A Superconductive Computer Component'' * 195A Cryotron Catalog Memory Systemby Al Slade and Howard McMahon * 1957 James W. Crowe application for U.S. paten''Superconducting Gating Devices'' Design As described by Buck, a straight wire of tantalum (having lower ''T''c) is wrapped around with a wire of niobium in a sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superconductivity
Superconductivity is a set of physical properties observed in superconductors: materials where Electrical resistance and conductance, electrical resistance vanishes and Magnetic field, magnetic fields are expelled from the material. Unlike an ordinary metallic Electrical conductor, conductor, whose resistance decreases gradually as its temperature is lowered, even down to near absolute zero, a superconductor has a characteristic Phase transition, critical temperature below which the resistance drops abruptly to zero. An electric current through a loop of superconducting wire can persist indefinitely with no power source. The superconductivity phenomenon was discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. Like ferromagnetism and Atomic spectral line, atomic spectral lines, superconductivity is a phenomenon which can only be explained by quantum mechanics. It is characterized by the Meissner effect, the complete cancellation of the magnetic field in the interior of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Field
A magnetic field (sometimes called B-field) is a physical 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, electric currents, and 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 (mathematics), function assigning a Euclidean vector, vector to each point of space, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tantalum
Tantalum is a chemical element; it has Symbol (chemistry), symbol Ta and atomic number 73. It is named after Tantalus, a figure in Greek mythology. Tantalum is a very hard, ductility, ductile, lustre (mineralogy), lustrous, blue-gray transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as components of strong superalloy, high-melting-point alloys. It is a group 5 element, along with vanadium and niobium, and it always occurs in geologic sources together with the chemically similar niobium, mainly in the mineral groups tantalite, columbite, and coltan. The chemical inertness and very high melting point of tantalum make it valuable for laboratory and industrial equipment such as Chemical reactor, reaction vessels and vacuum furnaces. It is used in tantalum capacitors for electronic equipment such as computers. It is being investigated for use as a material for high-quality superconducting resonators in quantum proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niobium
Niobium is a chemical element; it has chemical symbol, symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and Ductility, ductile transition metal. Pure niobium has a Mohs scale of mineral hardness, Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite. Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish. English chemist Charles Hatchett reported a new element similar to tantalum in 1801 and named it columbium. In 1809, English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. German chemist He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Helium
Liquid helium is a physical state of helium at very low temperatures at standard atmospheric pressures. Liquid helium may show superfluidity. At standard pressure, the chemical element helium exists in a liquid form only at the extremely low temperature of . Its boiling point and critical point depend on the isotope of helium present: the common isotope helium-4 or the rare isotope helium-3. These are the only two stable isotopes of helium. See the table below for the values of these physical quantities. The density of liquid helium-4 at its boiling point and a pressure of one atmosphere (101.3 kilopascals) is about , or about one-eighth the density of liquid water. Liquefaction Helium was first liquefied on July 10, 1908, by the Dutch physicist Heike Kamerlingh Onnes at the University of Leiden in the Netherlands. At that time, helium-3 was unknown because the mass spectrometer had not yet been invented. In more recent decades, liquid helium has been used as a cryogenic refriger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Electric
General Electric Company (GE) was an American Multinational corporation, multinational Conglomerate (company), conglomerate founded in 1892, incorporated in the New York (state), state of New York and headquartered in Boston. Over the years, the company had multiple divisions, including GE Aerospace, aerospace, GE Power, energy, GE HealthCare, healthcare, lighting, locomotives, appliances, and GE Capital, finance. In 2020, GE ranked among the Fortune 500, ''Fortune'' 500 as the 33rd largest firm in the United States by gross revenue. In 2023, the company was ranked 64th in the Forbes Global 2000, ''Forbes'' Global 2000. In 2011, GE ranked among the Fortune 20 as the 14th most profitable company, but later very severely underperformed the market (by about 75%) as its profitability collapsed. Two employees of GE—Irving Langmuir (1932) and Ivar Giaever (1973)—have been awarded the Nobel Prize. From 1986 until 2013, GE was the owner of the NBC television network through its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schenectady, New York
Schenectady ( ) is a City (New York), city in Schenectady County, New York, United States, of which it is the county seat. As of the United States Census 2020, 2020 census, the city's population of 67,047 made it the state's ninth-most populous city and the twenty-fifth most-populous municipality. The city is in eastern New York, near the confluence of the Mohawk River, Mohawk and Hudson River, Hudson rivers. It is in the same Capital District (New York), metropolitan area as the state capital, Albany, New York, Albany, which is about southeast. Schenectady was founded on the south side of the Mohawk River by Dutch colonists in the 17th century, many of whom came from the Albany area. The name "Schenectady" is derived from the Mohawk language, Mohawk word ''skahnéhtati'', meaning "beyond the pines" and used for the area around Albany, New York. Residents of the new village developed farms on strip plots along the river. Union College, the first non-denominational institut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrated Circuit
An integrated circuit (IC), also known as a microchip or simply chip, is a set of electronic circuits, consisting of various electronic components (such as transistors, resistors, and capacitors) and their interconnections. These components are etched onto a small, flat piece ("chip") of semiconductor material, usually silicon. Integrated circuits are used in a wide range of electronic devices, including computers, smartphones, and televisions, to perform various functions such as processing and storing information. They have greatly impacted the field of electronics by enabling device miniaturization and enhanced functionality. Integrated circuits are orders of magnitude smaller, faster, and less expensive than those constructed of discrete components, allowing a large transistor count. The IC's mass production capability, reliability, and building-block approach to integrated circuit design have ensured the rapid adoption of standardized ICs in place of designs using discre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels are present in the same crystal, they form a semiconductor junction. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called " metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others. Silicon is a critical element for fabricating most electronic circuits. Semiconductor devices can display a range of different useful properties, such as passing current more easil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josephson Junction
In physics, the Josephson effect is a phenomenon that occurs when two superconductors are placed in proximity, with some barrier or restriction between them. The effect is named after the British physicist Brian Josephson, who predicted in 1962 the mathematical relationships for the current and voltage across the weak link. :Also in It is an example of a macroscopic quantum phenomenon, where the effects of quantum mechanics are observable at ordinary, rather than atomic, scale. The Josephson effect has many practical applications because it exhibits a precise relationship between different physical measures, such as voltage and frequency, facilitating highly accurate measurements. The Josephson effect produces a current, known as a supercurrent, that flows continuously without any voltage applied, across a device known as a Josephson junction (JJ). These consist of two or more superconductors coupled by a weak link. The weak link can be a thin insulating barrier (known as a sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
