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Homes's Law
In superconductivity, Homes's law is an empirical relation that states that a superconductor's critical temperature (''T''c) is proportional to the strength of the superconducting state for temperatures well below ''T''c close to zero temperature (also referred to as the fully formed superfluid density, \rho_) multiplied by the electrical resistivity \rho_ measured just above the critical temperature. In cuprate high-temperature superconductors the relation follows the form : \rho_^\alpha\,\rho_^\alpha/8 \simeq 4.4\,T_c , or alternatively :\rho_^\alpha/8 \simeq 4.4\,\sigma_^\alpha\, T_c. Many novel superconductors are anisotropic, so the resistivity and the superfluid density are tensor quantities; the superscript \alpha denotes the crystallographic direction along which these quantities are measured. Note that this expression assumes that the conductivity and temperature have both been recast in units of cm−1 (or s−1), and that the superfluid density has units of cm−2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universal Scaling Line
Universal is the adjective for universe. Universal may also refer to: Companies * NBCUniversal, a media and entertainment company ** Universal Animation Studios, an American Animation studio, and a subsidiary of NBCUniversal ** Universal TV, a television channel owned by NBCUniversal ** Universal Kids, an American current television channel, formerly known as Sprout, owned by NBCUniversal ** Universal Pictures, an American film studio, and a subsidiary of NBCUniversal ** Universal Television, a television division owned by NBCUniversal Content Studios ** Universal Parks & Resorts, the theme park unit of NBCUniversal * Universal Airlines (other) * Universal Avionics, a manufacturer of flight control components * Universal Corporation, an American tobacco company * Universal Display Corporation, a manufacturer of displays * Universal Edition, a classical music publishing firm, founded in Vienna in 1901 * Universal Entertainment Corporation, a Japanese software produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superconductivity
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] |
Critical Temperature
Critical or Critically may refer to: *Critical, or critical but stable, medical states **Critical, or intensive care medicine *Critical juncture, a discontinuous change studied in the social sciences. *Critical Software, a company specializing in mission and business critical information systems *Critical theory, a school of thought that critiques society and culture by applying knowledge from the social sciences and the humanities * Critically endangered, a risk status for wild species *Criticality (status), the condition of sustaining a nuclear chain reaction Art, entertainment, and media * ''Critical'' (novel), a medical thriller written by Robin Cook * ''Critical'' (TV series), a Sky 1 TV series * "Critical" (''Person of Interest''), an episode of the American television drama series ''Person of Interest'' *"Critical", a 1999 single by Zion I People *Cr1TiKaL (born 1994), an American YouTuber and Twitch streamer See also *Critic *Criticality (other) *Critical Conditi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proportionality (mathematics)
In mathematics, two sequences of numbers, often experimental data, are proportional or directly proportional if their corresponding elements have a constant ratio, which is called the coefficient of proportionality or proportionality constant. Two sequences are inversely proportional if corresponding elements have a constant product, also called the coefficient of proportionality. This definition is commonly extended to related varying quantities, which are often called ''variables''. This meaning of ''variable'' is not the common meaning of the term in mathematics (see variable (mathematics)); these two different concepts share the same name for historical reasons. Two functions f(x) and g(x) are ''proportional'' if their ratio \frac is a constant function. If several pairs of variables share the same direct proportionality constant, the equation expressing the equality of these ratios is called a proportion, e.g., (for details see Ratio). Proportionality is closely rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zero Temperature
Absolute zero is the lowest limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reach their minimum value, taken as zero kelvin. The fundamental particles of nature have minimum vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion. The theoretical temperature is determined by extrapolating the ideal gas law; by international agreement, absolute zero is taken as −273.15 degrees on the Celsius scale (International System of Units), Note: The triple point of water is 0.01 °C, not 0 °C; thus 0 K is −2890.15 °C, not −273.16 °C. which equals −459.67 degrees on the Fahrenheit scale (United States customary units or Imperial units). The corresponding Kelvin and Rankine temperature scales set their zero points at absolute zero by definition. It is commonly thought of as the lowest temperature possible, but it is not the lowest ''enthalpy'' sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Resistivity
Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows electric current. Resistivity is commonly represented by the Greek letter (rho). The SI unit of electrical resistivity is the ohm-meter (Ω⋅m). For example, if a solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is , then the resistivity of the material is . Electrical conductivity or specific conductance is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter ( sigma), but (kappa) (especially in electrical engineering) and (gamma) are sometimes used. The SI unit of electrical conductivity is siemens per metre (S/m). Resistivity and conductivity are intensi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate causes of phenomena, and usually frame their understanding in mathematical terms. Physicists work across a wide range of research fields, spanning all length scales: from sub-atomic and particle physics, through biological physics, to cosmological length scales encompassing the universe as a whole. The field generally includes two types of physicists: experimental physicists who specialize in the observation of natural phenomena and the development and analysis of experiments, and theoretical physicists who specialize in mathematical modeling of physical systems to rationalize, explain and predict natural phenomena. Physicists can apply their knowledge towards solving practical problems or to developing new technologies (also known as applie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2019 ''Journal Citation Reports'' (with an ascribed impact factor of 42.778), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in autumn 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander Macmillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the journal; ''Nature'' redoubled its efforts in exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Zaanen
Jan Zaanen (born 17 April 1957) is professor of theoretical physics at Leiden University, the Netherlands. He is best known for his contributions to the understanding of the quantum physics of the electrons in strongly correlated material, and in particular high temperature superconductivity. Zaanen's areas of interest are in the search for novel forms of collective quantum phenomena realized in systems build from mundane constituents like electrons, spins, and atoms. He introduced the so-called Zaanen-Sawatzky-Allen diagram, the LDA+U band structure method and he became particularly well known for his discovery of the stripe instability of the doped Mott insulator. His present research is focused on the quantum critical point and unconventional phases of quantum matter. He is a well-known proponent of the application of Holographic principle to condensed matter physics. He is also well known for his many editorial contributions to the journals ''Nature'' and ''Science''. He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Review B
''Physical Review B: Condensed Matter and Materials Physics'' (also known as PRB) is a peer-reviewed, scientific journal, published by the American Physical Society (APS). The Editor of PRB is Laurens W. Molenkamp. It is part of the ''Physical Review'' family of journals. About the Physical Review Journals The current Editor in Chief is . PRB currently publishes over 4500 papers a year, making it one of the largest physics journals in the world. PRB ranked by the Eigenfactor, University of Washingto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephen Blundell
Stephen John Blundell (born 1967) is a professor of physics at the University of Oxford. He was previously head of Condensed Matter Physics at Oxford, and is also a professorial fellow of Mansfield College, Oxford. His research is concerned with using muon-spin rotation and magnetoresistance techniques to study a range of organic and inorganic materials, particularly those showing interesting magnetic, superconducting, or dynamical properties. Education Blundell completed both his undergraduate and graduate studies at the University of Cambridge, attending Peterhouse, Cambridge for his undergraduate degree in physics and theoretical physics and doing his PhD at the Cavendish Laboratory at Cambridge. Career and research He was subsequently offered a Science and Engineering Research Council (SERC) research fellowship which involved a move to the Clarendon Laboratory at Oxford; he was later awarded a junior research fellowship at Merton College, Oxford, where he began research in organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Superconductor
An organic superconductor is a synthetic organic compound that exhibits superconductivity at low temperatures. As of 2007 the highest achieved critical temperature for an organic superconductor at standard pressure is , observed in the alkali-doped fullerene RbCs2C60. In 1979 Klaus Bechgaard synthesized the first organic superconductor (TMTSF)2PF6 (the corresponding material class was named after him later) with a transition temperature of TC = 0.9 K, at an external pressure of 11 kbar. Many materials may be characterized as organic superconductors. These include the Bechgaard salts and Fabre salts which are both quasi-one-dimensional, and quasi-two-dimensional materials such as '' k-BEDT-TTF2X'' charge-transfer complex, '' λ-BETS2X'' compounds, graphite intercalation compounds and three-dimensional materials such as the alkali- doped fullerenes. Organic superconductors are of special interest not only for scientists, looking for room-temperature superconductivity and for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
