Image Antiferromagnetic ordering.svg thumb Antiferromagnetic ordering In materials that exhibit antiferromagnetism , the magnetic moment s of atom s or molecule s, usually related to the spins of electron s, align in a regular pattern with neighboring spin physics spins on different sublattices pointing in opposite directions. This is, like ferromagnetism and ferrimagnetism , a manifestation of ordered magnetism . Generally, antiferromagnetic order may exist at sufficiently low temperatures, vanishing at and above a certain temperature, the N el temperature named after Louis N el , who had first identified this type of magnetic ordering . ref L. N el, Propri t es magn tiques des ferrites F rrimagn tisme et antiferromagn tisme , Annales de Physique Paris 3, 137 198 1948 . ref Above the N el temperature, the material is typically paramagnetism paramagnetic . Measurement When no external field is applied, the antiferromagnetic structure corresponds to a vanishing total magnetization. In an external magnetic field, a kind of ferrimagnetic behavior may be displayed in the antiferromagnetic phase, with the absolute value of one of the sublattice magnetizations differing from that of the other sublattice, resulting in a nonzero net magnetization. The magnetic susceptibility of an antiferromagnetic material typically shows a maximum at the N el temperature. In contrast, at the transition between the ferromagnetism ferromagnetic to the paramagnetism paramagnetic phases the susceptibility will diverge. In the antiferromagnetic case, a divergence is observed in the staggered susceptibility . Various microscopic exchange interactions between the magnetic moments or spins may lead to antiferromagnetic structures. In the simplest case, one may consider an Ising model on an bipartite lattice ... Antiferromagnetism plays a crucial role in giant magnetoresistance , as had been discovered ... sk Antiferomagnetizmus fi Antiferromagnetismi sv Antiferromagnetism tr Antiferrom knat sl k ... more details
KCUF may refer to KGHT , a radio station 100.5 FM licensed to El Jebel, Colorado, United States, which held the call sign KCUF from August 2005 to June 2010 The call sign of a fictional radio station located in the equally fictional Kinneret, California in Thomas Pynchon s The Crying of Lot 49 In The Illuminatus Trilogy , Knights of Christianity United in Faith , likely as an homage to Pynchon s usage A number of internet radio stations call themselves KCUF A Punk rock punk band is named KCUF Potassium trifluorocuprate, KCuF sub 3 sub , is an antiferromagnetism antiferromagnetic perovskite structure perovskite in which unconfined spinon s have been observed disambig callsign ... more details
Unreferenced stub auto yes date December 2009 Helimagnetism is an incommensurate form of magnetic ordering that results from the competition between Ferromagnetic and Antiferromagnetic exchange interactions, and is typically only observed at liquid helium temperatures. Spins of neighbouring magnetic moments arrange themselves in a spiral or helical pattern, with a characteristic turn angle of somewhere between 0 and 180 degrees. It is possible to view Ferromagnetism and Antiferromagnetism as Helimagnetic structures with characteristic turn angles of 0 and 180 degrees respectively. Helimagnetic order breaks spatial inversion symmetry, as it can be either left handed or right handed in nature. magnetic states Category Magnetic ordering Condensedmatter stub fr H limagn tisme ... more details
The Morin transition also known as a spin flop transition is a magnetic phase transition in Fe sub 2 sub O sub 3 sub hematite where the antiferromagnetic ordering is reorganized from being aligned perpendicular to the c axis to be aligned parallel to the c axis below T sub M sub . T sub M sub 260K for Fe sup 3 sup in Fe sub 2 sub O sub 3 sub . A change in magnetic properties takes place at the Morin transition temperature. See also Ferromagnetism Antiferromagnetism Paramagnetism N el temperature References http flux.aps.org meetings YR00 MAR00 abs S240005.html American Physical Society abstract br Category Magnetism sl Morinov prehod ... more details
saved book title subtitle cover image cover color Magnetism Antiferromagnetism Biot Savart law Classical electromagnetism and special relativity Coercivity Diamagnetism Electromagnet Ferrimagnetism Ferromagnetism History of electromagnetic theory Lorentz force Magnet Magnetic bearing Magnetic circuit Magnetic dipole Magnetic domain Magnetic field Magnetic monopole Magnetic refrigeration Magnetic stirrer Magnetic structure Magnetism Metamagnetism Micromagnetics Molecule based magnets Neodymium magnet Paramagnetism Plastic magnet Rare earth magnet Single molecule magnet Spin glass Spin wave Spontaneous magnetization Superparamagnetism Vibrating sample magnetometer Category Wikipedia books on physics Magnetism ... more details
chembox verifiedrevid 367493807 Name Terbium silicide ImageFile ImageSize ImageName Terbium silicide IUPACName Terbium silicide OtherNames Terbium silicon br Silicon terbium br Terbium Disilicide Section1 Chembox Identifiers CASNo Section2 Chembox Properties Formula TbSi sub 2 sub MolarMass 215.09 g mol Appearance Gray powder Density Solubility Insoluble MeltingPt BoilingPt Section3 Chembox Structure MolShape Coordination CrystalStruct Orthorhombic or Hexagonal crystal system Hexagonal Dipole Section7 Chembox Hazards ExternalMSDS MainHazards Section8 Chembox Related OtherAnions OtherCations OtherCpds Rare Earth Silicides Terbium silicide is a chemical compound of the rare earth metal terbium with silicon having chemical formula TbSi sub 2 sub . It is a gray solid first described in detail in the late 1950 s. ref name Perri1959 cite doi 10.1021 j150574a041 ref The metallic resistivity and low Schottky barrier of TbSi sub 2 sub on N type semiconductor n type doped silicon make it a potential candidate for applications such as infrared detector s, ohmic contact s, Magnetoresistive Random Access Memory magnetoresistive devices , and Thermoelectric Devices and Materials thermoelectric devices . It exhibits antiferromagnetism at 16K. ref name Sekizawa1966 Cite journal author Sekizawa, K. Yasukochi, K. year 1966 title Antiferromagnetism of disilicides of heavy rare earth metals journal Journal of the Physical Society of Japan. volume 21 issue 2 pages 274 278 doi 10.1143 JPSJ.21.274 bibcode 1966JPSJ...21..274S postscript None ref References reflist Terbium compounds Category Silicides Category Terbium compounds fa ... more details
File Bethe Slater curve by Zureks.svg thumb Bethe Slater curve elements above the horizontal axis are ferromagnetic, below the axis are antiferromagnetic Bethe Slater curve is a chart graphical representation of exchange energy for transition metals as a function of the ratio of the interatomic distance a to the radius r of the 3d electron shell . ref http www.nitt.edu home academics departments physics faculty lecturers justin students magnetic exchange ref The curve illustrates why certain metals are ferromagnetism ferromagnetic and other antiferromagnetism antiferromagnetic . For a pair of atoms, the exchange interaction w sub ij sub responsible for the energy E is calculated as ref Soshin Chikazumi, Physics of Ferromagnetism, Oxford University Press, New York, 1997, page 125, ISBN 0 19 851776 9 ref math w ij 2 cdot J cdot S i cdot S j math where J exchange integral, S electron spins, i and j indices of the two atoms. References reflist Category Magnetism de Bethe Slater Kurve pl Krzywa Bethe Slatera ... more details
Antiferroelectricity is a physical property of certain materials. It is closely related to ferroelectricity the relation between antiferroelectricity and ferroelectricity is analogous to the relation between antiferromagnetism and ferromagnetism . An antiferroelectric material consists of an ordered crystal line array of electric dipole s from the ions and electrons in the material , but with adjacent dipoles oriented in opposite antiparallel directions the dipoles of each orientation form interpenetrating sublattices, loosely analogous to a checkerboard pattern . ref http www.iupac.org goldbook F02347.pdf IUPAC goldbook ref ref C. Kittel, Theory of Antiferroelectric Crystals , Phys. Rev. 82, 729 732 1951 . http dx.doi.org 10.1103 PhysRev.82.729 DOI web link ref This can be contrasted with a ferroelectric, in which the dipoles all point in the same direction. In an antiferroelectric, unlike a ferroelectric, the total, macroscopic polarization density spontaneous polarization is zero, since the adjacent dipoles cancel each other out. Antiferroelectricity is a phase matter phase of a material, and it can appear or disappear more generally, strengthen or weaken depending on temperature, pressure, external electric field, growth method, and other parameters. In particular, at a high enough temperature, antiferroelectricity disappears this temperature is called the antiferroelectric Curie point . ref See, for example, C. Pulvari, Ferrielectricity, Phys. Rev. 120, 1670 1673 1960 http dx.doi.org 10.1103 PhysRev.120.1670 DOI web link ref References reflist Polarization states material stub Category Condensed matter physics Category Electrical phenomena fr Antiferro lectricit kk ru uk ... more details
saved book title subtitle cover image cover color Engineering A Computer Based Generative Model for Studying Proposed Development Paradigms of Life in the Early Solar System Reference Material Handbook Artificial life Breve software Dynamical simulation Collision detection Galaxy morphological classification Morphology biology Taxon Geomorphology Mathematical morphology Opening morphology Translational symmetry Hit or miss transform Pruning morphology Morphological skeleton Granulometry morphology Liquid State of matter Pressure Temperature Matter Baryon Atom List of particles Elementary particle Fermion Quark Lepton Hyperon Strange quark Hypernucleus Exotic baryon Pentaquark Strong interaction Meson Boson Quark model Quantum chromodynamics Gluon Particle physics Particle accelerator Collision Nuclear physics Quantum field theory Condensed matter physics Ferromagnetism Antiferromagnetism Crystal structure Bose Einstein condensate Higgs boson Large Hadron Collider Electron List of baryons Neutrino Neutron Weak interaction Spin physics Standard Model Proton Gravitation Hadron Atomic nucleus Quantum mechanics Antiparticle Subatomic particle Nucleon Photon Fundamental interaction Pauli exclusion principle Isospin Physics W and Z bosons Mass CERN Flavour particle physics Gauge boson ... more details
and antiferromagnetism . In 1948 they developed a consistent theoretical polar model of metals ... important contribution to antiferromagnetism was in the development of the method of quantum ... more details
Use dmy dates date September 2010 Timeline of states of matter and phase transitions 1895 Pierre Curie discovers that induced magnetization is proportional to magnetic field strength 1911 Heike Kamerlingh Onnes discloses his research on superconductivity 1912 Peter Debye derives the T cubed law for the low temperature heat capacity of a nonmetallic solid 1925 Ernst Ising presents the solution to the one dimensional Ising model 1928 Felix Bloch applies quantum mechanics to electronic band structure electrons in crystal lattices , establishing the quantum theory of solids 1929 Paul Dirac Paul Adrien Maurice Dirac and Werner Karl Heisenberg develop the quantum theory of ferromagnetism 1932 Louis N el Louis Eug ne F lix Neel discovers antiferromagnetism 1933 Walter Meissner and Robert Ochsenfeld discover perfect superconducting diamagnetism 1933 1937 Lev Davidovich Landau develops the Landau theory of phase transition s 1937 Pyotr Leonidovich Kapitsa and John Frank Allen discover superfluid ity 1941 Lev Davidovich Landau explains superfluid ity 1942 Hannes Alfven predicts magnetohydrodynamics magnetohydrodynamic waves in plasmas 1944 Lars Onsager publishes the exact solution to the two dimensional Ising model 1957 John Bardeen , Leon Cooper , and Robert Schrieffer develop the BCS theory of superconductivity End of the 50s Lev Davidovich Landau develops the theory of Fermi liquid 1959 Philip Warren Anderson predicts Anderson localization localization in disordered systems 1972 Douglas Osheroff , Robert Coleman Richardson Robert C. Richardson , and David Lee physicist David Lee discover that helium 3 can become a superfluid 1974 Kenneth G. Wilson develops the renormalization group technique for treating phase transitions 1980 Klaus von Klitzing discovers the quantum Hall effect 1982 Horst L. Stoermer and Daniel C. Tsui discover the fractional quantum Hall effect 1983 Robert B. Laughlin explains the fractional quantum Hall effect 1987 Karl Alexander M ller and Georg Bednor ... more details
AFM may refer to TOC right Organizations AFM Records , a German record label Africa Fighting Malaria , a health campaign in Africa Alex von Falkenhausen Motorenbau , a German racing car constructor American Federation of Motorcyclists , a road racing club in the United States American Federation of Musicians , a labor union of musicians in North America American Film Market , an annual event for the financing of film production and distribution American Freedom Mortgage, Inc. , a corporation based in Georgia, U.S. Autoriteit Financi le Markten , Netherlands financial markets regulator Macau Football Association , the governing body of football in Macau Armed Forces of Malta , the name given to the combined armed services of Malta Publications Aquarium Fish Magazine , a North American monthly magazine Annals of the Four Masters , a chronicle of medieval Irish history Science and technology AFM gene , in biochemistry, a member of the albumin gene family that encodes the protein Afamin Abrasive Flow Machining , a technique for smoothing internal part surfaces Active Fuel Management formerly Displacement on Demand , is a trademarked name for the automobile variable displacement technology from General Motors Adobe Font Metrics , a computer file format Air flow meter , a device that measures how much air is flowing through a tube AFm phase , or Alumina, Ferric oxide, monosulfate phase, in chemistry Antiferromagnetism , a material property and type of magnetic ordering Atomic force microscope , a high resolution type of scanning probe microscope Audio Frequency Modulation , an audio recording standard Military Air Force Medal , awarded in the Royal Air Force United Kingdom United States Air Force Memorial , in Arlington, Virginia disambig de AFM fr AFM it AFM nl AFM ja AFM no AFM pl AFM pt AFM sv AFM fi AFM ... more details
DISPLAYTITLE 5 Dehydro m xylylene chembox verifiedrevid 366685457 Name 5 Dehydro m xylylene ImageFile DMX line.png ImageSize 150px ImageName 5 Dehydro m xylylene IUPACName 5 dehydro 1,3 quinodimethane OtherNames 5 dehydro m xylylene, br DMX Section1 Chembox Identifiers CASNo 681440 83 5 Section2 Chembox Properties Formula C sub 8 sub H sub 7 MolarMass 103.14 g mol 5 Dehydro m xylylene DMX is an aromaticity aromatic organic chemistry organic free radical triradical and the first known organic molecule to violate Hund s rule of maximum multiplicity Hund s Rule . ref cite journal author L Slipchenko et al. title 5 Dehydro 1,3 quinodimethane A Hydrocarbon with an Open Shell Doublet Ground State journal Angewandte Chemie International Edition year 2004 volume 43 pages 742 doi 10.1002 anie.200352990 pmid 14755709 issue 6 ref Its electronic ground state is an open shell open shell doublet rather than a quartet that is, it contains three low Spin physics spin coupled unpaired electrons in three singly occupied molecular orbital s. Because there are radical electrons in both spin states, this compound is said to exhibit antiferromagnetism . Though similar ground states are observed in molecules containing transition metal atoms, it is unprecedented in organic molecules. The 5 dehydro m xylylene anion DMX sup sup has also been studied extensively. It has a triplet ground state consisting of a phenyl anion and a m xylylene biradical . References references External links http physicsweb.org articles news 8 2 5 Physics web Radical molecule breaks the rules http www.chem.purdue.edu NewsFeed newsstory.asp?itemID 94 Purdue University Department of Chemistry Rule breaking molecule http www rcf.usc.edu krylov Publications PDFs CEN dmx.html Triradical breaks the rules http www.usc.edu schools college college magazine may 2004 krylov.html A discovery that breaks the laws of chemistry http www.compchemwiki.org index.php?title 5 dehydro m xylylene Computational Chemistry Wiki DEFAULTSOR ... more details
In statistical physics , the axial or anisotropic next nearest neighbor Ising model , usually known as the ANNNI model , is a variant of the Ising model in which competing ferromagnetism ferromagnetic and antiferromagnetism antiferromagnetic exchange interaction s couple spin physics spins at nearest and next nearest neighbor sites along one of the crystallographic axes of the Bravais lattice lattice . The model is a prototype for complicated spatially modulated magnetic superstructure s in crystal s. The model was introduced in 1961 by Roger Elliott physicist Roger Elliott from the University of Oxford , but only given this name in 1980 by Michael E. Fisher and Walter Selke . It provides a theoretical basis for understanding numerous experimental observations on commensurability mathematics commensurate and commensurability mathematics incommensurate structures, as well as accompanying phase transition s, in magnet s, alloy s, adsorbate s, and other solid s. References cite journal author R. J. Elliott authorlink Roger Elliott physicist year 1961 title Phenomenological discussion of magnetic ordering in the heavy rare earth metals journal Phys. Rev. volume 124 pages 346&ndash 353 doi 10.1103 PhysRev.124.346 bibcode 1961PhRv..124..346E issue 2 cite journal author Michael E. Fisher M.E. Fisher and Walter Selke W. Selke year 1980 title Infinitely many commensurate phases in a simple Ising model journal Phys. Rev. Lett. volume 44 pages 1502&ndash 1505 doi 10.1103 PhysRevLett.44.1502 bibcode 1980PhRvL..44.1502F issue 23 cite journal author Per Bak P. Bak year 1982 title Commensurate phases, incommensurate phases, and the devil s staircase journal Reports on Progress in Physics volume 45 pages 587&ndash 629 doi 10.1088 0034 4885 45 6 001 bibcode 1982RPPh...45..587B issue 6 cite journal author Walter Selke W. Selke year 1988 title The ANNNI model Theoretical analysis and experimental application journal Physics Reports volume 170 pages 213&ndash 264 doi 10.1016 0370 1573 ... more details
Herbert Wagner born 6 April 1935 is a German theoretical physicist, who mainly works in statistical mechanics . He is a professor emeritus of Ludwig Maximilian University of Munich . TOC Biography Wagner was one of the last students of German theoretical physicist and Nobel prize winner Werner Heisenberg , with whom he worked on magnetism. ref W. Heisenberg, H. Wagner, K. Yamazaki Magnons in a model with antiferromagnetic properties , Il Nuovo Cimento 59, 377 391 1969 , doi 10.1007 BF02755024 . ref As a postdoc at Cornell University , he and David Mermin and independently of Pierre Hohenberg proved a no go theorem , otherwise known as the Mermin Wagner theorem . The theorem states that continuous symmetries cannot be spontaneous symmetry breaking spontaneously broken at finite temperature in systems with sufficiently short range interactions in dimensions math d le 2 math . ref N.D. Mermin, H. Wagner Absence of Ferromagnetism or Antiferromagnetism in One or Two Dimensional Isotropic Heisenberg Models , Phys. Rev. Lett. 17, 1133 1136 1966 . ref Wagner is the academic father of a generation of statistical physicists. Many of his students and junior collaborators now occupy chairs in German universities, including Hans Werner Diehl Essen , Siegfried Dietrich Wuppertal, then Stuttgart , Klaus Mecke Erlangen , Reinhard Lipowsky Max Planck Institute of Colloids and Interfaces, Berlin , Hartmut L wen D sseldorf and Udo Seifert Stuttgart . Awards In 1992, Wagner was awarded an honorary degree by the University of Essen now University of Duisburg Essen . ref http www.theo phys.uni essen.de tp Ehrenpromotionen.html Ehrenpromotionen in der Theoretischen Physik an der Universit t & 91 Duisburg & 93 Essen ref References reflist Persondata Metadata see Wikipedia Persondata . NAME Wagner, Herbert ALTERNATIVE NAMES SHORT DESCRIPTION German physicist DATE OF BIRTH 6 April 1935 PLACE OF BIRTH DATE OF DEATH PLACE OF DEATH DEFAULTSORT Wagner, Herbert Category German physicists Category ... more details
Not to be confused with Ferromagnetism for an overview see Magnetism Image Ferrimagnetic ordering.svg thumb Ferrimagnetic ordering In physics , a ferrimagnetic material is one in which the magnetic moment s of the atoms on different sublattice s are opposed Cn reason Need English language secondary source date September 2011 , as in antiferromagnetism however, in ferrimagnetic materials, the opposing moments are unequal and a spontaneous magnetization remains. This happens when the sublattices consist of different materials or ion s such as Fe sup 2 sup and Fe sup 3 sup . Ferrimagnetism is exhibited by Ferrite magnet ferrite s and magnetic garnets. The oldest known magnetic substance, magnetite iron II,III oxide Iron Fe sub 3 sub Oxygen O sub 4 sub , is a ferrimagnet it was originally classified as a ferromagnet before Louis N el N el s discovery of ferrimagnetism and antiferromagnetism in 1948. ref L. N el, Propri t es magn tiques des ferrites F rrimagn tisme et antiferromagn tisme , Annales de Physique Paris 3, 137 198 1948 . ref Some ferrimagnetic materials are YIG yttrium iron garnet and ferrites composed of iron oxide s and other elements such as aluminum , cobalt , nickel , manganese and zinc . Effects of temperature Image Ferrimagnetism magnetic moment as a function of temperature.svg thumb right 185px Below the magnetization compensation point, ferrimagnetic material is magnetic. At the compensation point, the magnetic components cancel each other and the total magnetic moment is zero. Above the Curie temperature Curie point , material loses magnetism. Ferrimagnetic materials are like ferromagnetism ferromagnets in that they hold a spontaneous magnetization below the Curie temperature , and show no magnetic order are paramagnetic above this temperature. However, there is sometimes a temperature below the Curie temperature at which the two sublattices have equal moments, resulting in a net magnetic moment of zero this is called the magnetization compensation ... more details
expert subject physics date March 2009 In physics, the term clusters denotes small, multiatom particles. As a rule of thumb, any particle of somewhere between 3 and 3x10 sup 7 sup atom s is considered a cluster. Two atom particles are sometimes considered clusters as well Fact date February 2007 . The term can also refer to the organization of protons and neutrons within an atomic nucleus, e.g. the Alpha particle a.k.a. as http arxiv.org PS cache arxiv pdf 0906 0906.3556v2.pdf cluster , consisting of two protons and two neutrons as in a helium nucleus . Although first reports of cluster species date back already to the 1940s ref name hahn cite journal author Mattauch J, Ewald H, Hahn O, Strassmann F. title Hat ein Caesum Isotop langer Halbwertszeit existiert? Ein Beitrag zur Deutung ungew hnlicher Linien in der Massenspektrographie journal Zeitschrift f r Physik volume 120 pages 598 617 year 1943 bibcode 1943ZPhy..120..598M doi 10.1007 BF01329807 issue 7 10 ref , Cluster science emerged as a separate direction of research in the 1980s, One purpose of the research was to study the gradual development of collective phenomena which characterize a bulk solid. These are for example the color of a body, its electrical conductivity, its ability to absorb or reflect light, and magnetic phenomena such as ferro , ferri , or antiferromagnetism. These are typical collective phenomena which only develop in an aggregate of a large number of atoms. It was found that collective phenomena break down for very small cluster sizes. It turned out, for example, that small clusters of a ferromagnetic material are super paramagnetic rather than ferromagnetic. Paramagnetism is not a collective phenomenon, which means that the ferromagnetism of the macrostate was not conserved by going into the nanostate. The question then was asked for example How many atoms do we need in order to obtain the collective metallic or magnetic properties of a solid ? Soon after the first cluster sources had b ... more details
The Classical Heisenberg model is the math n 3 math case of the n vector model , one of the models used in statistical physics to model ferromagnetism , and other phenomena. Definition It can be formulated as follows take a d dimensional lattice group lattice , and a set of spins of the unit length math vec s i in mathbb R 3, vec s i 1 quad 1 math , each one placed on a lattice node. The model is defined through the following Hamiltonian mechanics Hamiltonian math mathcal H sum i,j mathcal J ij vec s i cdot vec s j quad 2 math with math mathcal J ij begin cases J & mbox if i, j mbox are neighbors 0 & mbox else. end cases math a coupling between spins. Properties Polyakov has conjectured that, in dimension 2, as opposed to the classical XY model , there is no dipole phase for any math T 0 math i.e. at non zero temperature the correlations cluster exponentially fast. ref cite journal last Polyakov first A.M. journal Phys.Letts. year 1975 volume B 59 url http www.sciencedirect.com science article pii 0370269375901616 doi 10.1016 0370 2693 75 90161 6 bibcode 1975PhLB...59...79P ref The general mathematical formalism used to describe and solve the Heisenberg model and certain generalizations is developed in the article on the Potts model . In the continuum limit the Heisenberg model 2 gives the following equation of motion math vec S t vec S wedge vec S xx . math This equation is called the continuous classical Heisenberg ferromagnet equation or shortly Heisenberg model and is integrable in the soliton sense. It admits several integrable and nonintegrable generalizations like Landau Lifshitz equation , Ishimori equation and so on. See also Heisenberg model quantum Ising model Classical XY model Magnetism Ferromagnetism Landau Lifshitz equation Ishimori equation References reflist External links http prola.aps.org abstract PRL v17 i22 p1133 1 Absence of Ferromagnetism or Antiferromagnetism in One or Two Dimensional Isotropic Heisenberg Models http www.math.ucdavis.edu bxn ... more details
Image Shubnikv.JPG right 250px thumb Lev Shubnikov Lev Vasilyevich Shubnikov lang ru lang uk September 9, 1901&mdash November 10, 1937 was a USSR Soviet experimental physicist who worked in the Netherlands and USSR . Shubnikov was born into the family of a Saint Petersburg accountant. After graduating from a Gymnasium school gymnasium he entered Saint Petersburg State University Leningrad University . This was the first year of the Russian Civil War and he was the only student of that year attending the physics department. While yachting in the Gulf of Finland in 1921, he accidentally sailed from Saint Petersburg to Finland , was sent to Germany and could not return to Russia until 1922. He then continued his education in the Leningrad Polytechnical Institute , graduating in 1926. During his university training he worked with Ivan Obreimov , developing a new method for growing monocrystal s of metals. In 1926, at the recommendation of Abram Ioffe , he was sent to the Leiden cryogenic laboratory of Wander Johannes de Haas in the Netherlands he worked there until 1930. Shubnikov studied bismuth crystals with low impurity concentrations, and in cooperation with Wander Johannes de Haas he discovered magnetoresistance oscillations at low temperatures in magnetic field s the Shubnikov De Haas effect . The importance of this effect for condensed state physics became completely clear only much later. Today this effect is one of the principal instruments used in studying the quantum electron properties of solids. In 1930 Shubnikov returned to Kharkov and established there the first Soviet cryogenic laboratory. He also discovered the antiferromagnetism in 1935 and paramagnetism in 1936, together with Boris Lazarev of solid state hydrogen . He was one of the first to study liquid helium . In 1937, at the height of the Great Purge , the NKVD launched the UPTI Affair Ukrainian Physics and Technology Institute Affair on the basis ... more details
orphan date January 2011 Lattice density functional theory LDFT is a statistical theory used in physics and thermodynamics to model a variety of physical phenomena with simple Lattice model physics lattice equations. Lattice models with nearest neighbor interactions have been used extensively to model a wide variety of systems and phenomena, including the lattice gas, binary liquid solutions, order disorder phase transitions , ferromagnetism , and antiferromagnetism ref Hill TL. Statistical Mechanics, Principles and Selected Applications. New York Dover Publications 1987. ref . Most calculations of correlation functions for nonrandom configurations are based on statistical mechanical techniques, which lead to equations that usually need to be solved numerically. In 1925, Ernst Ising Ising ref Ising E. Report on the theory of ferromagnetism. Zeitschrift Fur Physik, 31, 253 1925 . ref gave an exact solution to the one dimensional 1D lattice problem. In 1944 Lars Onsager Onsager ref Onsager L. Crystal statistics I A two dimensional model with an order disorder transition. Physical Review, 65, 117 1944 . ref was able to get an exact solution to a two dimensional 2D lattice problem at the critical density. However, to date, no three dimensional 3D problem has had a solution that is both complete and exact ref Hill TL. An introduction to statistical thermodynamics, New York, Dover Publications 1986 . ref . Over the last ten years, Aranovich and Donohue have developed lattice density functional theory LDFT based on a generalization of the Ono Kondo equations to three dimensions, and used the theory to model a variety of physical phenomena. The theory starts by constructing an expression for Thermodynamic free energy free energy , A U TS, where internal energy U and entropy S can be calculated using mean field approximation. The grand potential is then constructed as A , where is a Lagrange multiplier which equals to the chemical potential , and is a constraint give ... more details
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