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Josephson Voltage Standard
A Josephson voltage standard is a complex system that uses a superconducting integrated circuit chip operating at a temperature of 4 K to generate stable voltages that depend only on an applied frequency and fundamental constants. It is an intrinsic standard in the sense that it does not depend on any physical artifact. It is the most accurate method to generate or measure voltage and, by international agreement in 1990, is the basis for voltage standards around the world. Josephson effect In 1962, Brian Josephson, a graduate student at Cambridge University, derived equations for the current and voltage across a junction consisting of a thin insulating barrier separating two superconductors – now generally known as a Josephson junction. His equations predicted that if a junction is driven at frequency f , then its current–voltage (I–V) curve will develop regions of constant voltage at the values nhf/2e , where n is an integer and h/e is the ratio of the Planck ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brian Josephson
Brian David Josephson (born 4 January 1940) is a Welsh theoretical physicist and professor emeritus of physics at the University of Cambridge. Best known for his pioneering work on superconductivity and quantum tunnelling, he was awarded the Nobel Prize in Physics in 1973 for his prediction of the Josephson effect, made in 1962 when he was a 22-year-old PhD student at Cambridge University. Josephson is the only Welshman to have won a Nobel Prize in Physics. He shared the prize with physicists Leo Esaki and Ivar Giaever, who jointly received half the award for their own work on quantum tunnelling."Brian D. Josephson" ''Encyclopædia Britannica''. Josephson has spent his academic career as a member of the Theory of Condensed Matter group at Cambridge's |
Layout And Schematic Of JVS Chip
Layout may refer to: * Page layout, the arrangement of visual elements on a page ** Comprehensive layout (comp), a proposed page layout presented by a designer to their client * Layout (computing), the process of calculating the position of objects in space * Layout engine, another name for web browser engine, the core software that displays content in a web browser * Automobile layout, a description of the locations of the engine and drive wheels on a vehicle * Integrated circuit layout, the representation of an integrated circuit in geometric shapes * Keyboard layout, an arrangement of the keys on a typographic keyboard * Model railroad layout, a diorama with tracks for operating scaled-down trains *Layout (dominoes), the tableau in a domino game * Layout or marking out, the transfer of a design onto a workpiece in manufacturing * Plant layout study, an engineering study to analyze physical configurations for a manufacturing plant * Layout, a specific version of the splits, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measurement Loop Diagram
Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to a basic reference quantity of the same kind. The scope and application of measurement are dependent on the context and discipline. In natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the ''International vocabulary of metrology'' published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales. Measurement is a cornerstone of trade, science, technology and quantitative research in many disciplines. Historically, many measurement systems existed for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bias System For A Josephson Voltage Standard
Bias is a disproportionate weight ''in favor of'' or ''against'' an idea or thing, usually in a way that is closed-minded, prejudicial, or unfair. Biases can be innate or learned. People may develop biases for or against an individual, a group, or a belief. In science and engineering, a bias is a systematic error. Statistical bias results from an unfair sampling of a population, or from an estimation process that does not give accurate results on average. Etymology The word appears to derive from Old Provençal into Old French ''biais'', "sideways, askance, against the grain". Whence comes French ''biais'', "a slant, a slope, an oblique". It seems to have entered English via the game of bowls, where it referred to balls made with a greater weight on one side. Which expanded to the figurative use, "a one-sided tendency of the mind", and, at first especially in law, "undue propensity or prejudice". Types of bias Cognitive biases A cognitive bias is a repeating or basic misst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josephson Voltage Standard Block Diagram
Josephson is a patronymic surname meaning "son of Joseph". Notable people with the surname include: * Andy Josephson (born 1964), American lawyer and politician * Brian David Josephson (born 1940), Welsh physicist * Duane Josephson (1942–1997), American baseball player * Erland Josephson (1923–2012), Swedish actor and author * Erik Josephson (1864–1929), Swedish architect * Ernst Josephson (1851–1906), Swedish painter * Ian Josephson, Canadian judge * Julien Josephson (1881–1959), American motion picture screenwriter * Karen Josephson (born 1964), American swimmer * Les Josephson (1942–2020), American football player * Mark Josephson (1943–2017), American cardiac electrophysiologist * Matthew Josephson (1899–1978), American journalist and author * Samantha Josephson (died 2019), American murder victim * Sarah Josephson (born 1964), American swimmer * Timothy Josephson, American politician See also * Josephson effect, used in quantum-mechanical circuits, with re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Silver
Nickel silver, Maillechort, German silver, Argentan, new silver, nickel brass, albata, alpacca, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver does not contain the element silver. It is named for its silvery appearance, which can make it attractive as a cheaper and more durable substitute. It is also well suited for being plated with silver. A naturally occurring ore composition in China was smelted into the alloy known as or () ("white copper" or cupronickel). The name "German Silver" refers to the artificial recreation of the natural ore composition by German metallurgists.Joseph Needham, Ling Wang, Gwei-Djen Lu, Tsuen-hsuin Tsien, Dieter Kuhn, Peter J Golas''Science and civilisation in China'' Cambridge University Press: 1974, , pp. 237–250 All modern, commercially important, nickel silvers (such as those standardized under ASTM B122) contain significant amounts of zinc and are sometimes considered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Finline
Planar transmission lines are transmission lines with electrical conductor, conductors, or in some cases dielectric (insulating) strips, that are flat, ribbon-shaped lines. They are used to interconnect components on printed circuits and integrated circuits working at microwave frequencies because the planar type fits in well with the manufacturing methods for these components. Transmission lines are more than simply electrical cable, interconnections. With simple interconnections, the propagation of the electromagnetic wave along the wire is fast enough to be considered instantaneous, and the voltages at each end of the wire can be considered identical. If the wire is longer than a large fraction of a wavelength (one tenth is often used as a rule of thumb), these assumptions are no longer true and Telegrapher's equations, transmission line theory must be used instead. With transmission lines, the geometry of the line is precisely controlled (in most cases, the cross-section i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waveguide
A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities decrease according to the inverse square law as they expand into three-dimensional space. There are different types of waveguides for different types of waves. The original and most common meaningInstitute of Electrical and Electronics Engineers, “The IEEE standard dictionary of electrical and electronics terms”; 6th ed. New York, N.Y., Institute of Electrical and Electronics Engineers, c1997. IEEE Std 100-1996. d. Standards Coordinating Committee 10, Terms and Definitions; Jane Radatz, (chair)/ref> is a hollow conductive metal pipe used to carry high frequency radio waves, particularly microwaves. Dielectric waveguides are used at higher radio frequencies, and transparent dielectric waveguides and optical fibers serve as waveguides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Layout Of A 10 V JVS Chip
Layout may refer to: * Page layout, the arrangement of visual elements on a page ** Comprehensive layout (comp), a proposed page layout presented by a designer to their client * Layout (computing), the process of calculating the position of objects in space * Layout engine, another name for web browser engine, the core software that displays content in a web browser * Automobile layout, a description of the locations of the engine and drive wheels on a vehicle * Integrated circuit layout, the representation of an integrated circuit in geometric shapes * Keyboard layout, an arrangement of the keys on a typographic keyboard * Model railroad layout, a diorama with tracks for operating scaled-down trains *Layout (dominoes), the tableau in a domino game * Layout or marking out, the transfer of a design onto a workpiece in manufacturing * Plant layout study, an engineering study to analyze physical configurations for a manufacturing plant * Layout, a specific version of the splits, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superconductors
Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic flux fields are expelled from the material. Any material exhibiting these properties is a superconductor. Unlike an ordinary metallic conductor, whose resistance decreases gradually as its temperature is lowered even down to near absolute zero, a superconductor has a characteristic 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 lines, superconductivity is a phenomenon which can only be explained by quantum mechanics. It is characterized by the Meissner effect, the complete ejection of magnetic field lines from the interior of the superconductor during its transitions into the sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
