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Superconductivity Pramana Research Journal ISSN NO: 2249-2976 SUPERCONDUCTIVITY: A REVIEW 1Rajiv Khullar, 2Ankit Pal Singh, 3Harshil Abhijeet 1Assistant Professor, Department of Mechanical Engineering, Chandigarh University, Punjab 2,3B.E Student, Department of Mechanical Engineering, Chandigarh University, Punjab [email protected],[email protected] Abstract What if superconductors could work on room temperature? There is a reason for asking this silly question that, if thisthing happen then we will have “a new technological revolution.” That is superconductor can transmit electrical current with absolutely no loss of energy. If scientists could bring that at room temperature then we can replace any thing requiring electricity, including the large power grids. INTRODUCTION Superconductivity could be a development of specifically zero electrical resistant and expulsion of magnetic flux field occuring in bound material referred to as superconductors, once these materials ar cooled down below a characteristic important temperature. It absolutely was discovered by Dutch scientist Heike Kamerling Onnes on April eight,1911, in Leiden. Like magnetism and atomic field lines, it's associate degree quantum physical phenomenon. it's characterised as Meissner result.The complete removing out of the magnetic lines from the inside of the superconductor throughout the transition into superconductor state. incidence of Meissner result indiccates the electrical conduction can't be understood merely because the idealisation of good physical phenomenon by classical medication. The resistance of gold conductors decreases usually because the temperature is lowered . In standard conductors like copper and silver, the decreases is proscribed by impurities and alternative defects. Even close to temperature, rare sample of traditional conductors show some resistance however in superconductors the resistacnce drop suddenly to zeroas the fabric is cooled below important temperature. A electrical current through the loops of superconducting wire will persist indefinately with no power supply.[1][2][3][4] SUPERCONDUCTING MATERIAL Superconductor material categories embrace chemical components , alloys , ceramic, superconducting pnictides or organic superconductors(carbon nanotubes and fullerenes; although perhaps these examples need to be clathrate among the chemical components).[15] HISTORY OF SUPERCONDUCTIVITY Superconductivity was discovered on Apr eight, 1911 by Heike Kamerlingh Onnes, World Health Organization was finding resisting solid mercury at refrigerant temperatures exploitation currently created the liquid. At the temperature of four.2 K, he discovered that the resistance dead disappeared. within the identical experiment, he conjointly discovered the superfluid transition of Helium,argon,inert gases and noble gases at 2.2 K, which not allow their significance.[5][6] Volume 8, Issue 3, 2018 44 https://pramanaresearch.org/ Pramana Research Journal ISSN NO: 2249-2976 Many attempts are dedicated to sorting out how it being process and why electrical conduction works; the necessary step occurred in 1933,Ochsenfeld and Meissner found that applied magnetic fields is expelled by supeconductors, a development that has return that called the Meissner result. [7][8] HIGH-TEMPERATURE SUPERCONDUCTIVITY Till 1986, physicists had believed that BCS theory forbade electrical conduction at temperatures higher than concerning thirty K. there in year, Muller and Bednorz light on the electrical conduction during lanthanum based material, like cuprte perovskite, that had a conversion temperature of thirty five K (Nobel Prize in Physics, 1987). it had been shortly found that commutation the metallic element with metallic element (i.e., creating YBCO) raised the important temperature to ninety two K.[9] This temperature jump is especially important, since it permits liquid nitorgen as a refrigerant, commutation liquid argonon. this could be vital commercially as a result of cryogen may be made comparatively cheaply, even on-the-scene. Also, the upper temperatures facilitate avoid a number of the issues that arise at liquid argonon temperatures, like the development of frozen air plugs which may pause refrigerant pipes and creates the doubtless and unexcepted venturous pressure buildup.[10] In Gregorian calendar month two thousand eight the associate degree high-temperature superconductors which was based on the family of iron-based.Hideo Hosono, of the Tokio Technology Institute, and found metallic element gas F iron compound (LaO1−xFxFeAs), associate degree oxypnictide that superconducts below twenty six K. Commutation the metallic element in LaO1−xFxFeAs with metallic element ends up in superconductors that job at fifty five K.[11] In could 2014, hydrofen chemical compound (H2S) was perdicted to be a heat superconductor with a transition temperature of 80K at 10 GPa of pressure. In the year 2015, H2S has determined to give away electrical conduction unnder the temperature of 203K, however extraordinarily high pressures around a hundred and fifty gigapascals. In 2018, the Department of Physics, Massachusetts Institute of Technology, got that the bilayer graphene that have electric conduction which is twisted at associate degree of roughly angle one degrees with applying a little changes and cooling. Notwithstanding this type of experiments weren't dispensed during a surrounding of high temperature, result of the area unit are correlative less to classical however heat superconductors, on condition that no foreign atoms ought to be introduced.[12] APPLICATION Superconducting magnets area unit a number of the foremost powerful magnet well-known. they're employed in mass spectrometers,machine like MRI/NMR,particle accelerators in which the beam- steeing magnets and some tokamaks that have plasma confining magnets. They'll even be used for separation of magnetic, wherever feeble magnetic particles area unit extracted from a background of less or non-magnetic particles, as within the pigment industries.[15] In 1950’s, superconductors are not to build experiment things like digital computers victimization cryoton switches.Currently,superconductors are wont to create digital circuits supported fast single flux quantum technology and RF and microwave filters for itinerant base stations.[13] UNLEASING DIFFERENT TECHNOLOGIES BY BRING AT ROOM TEMPEATURE Volume 8, Issue 3, 2018 45 https://pramanaresearch.org/ Pramana Research Journal ISSN NO: 2249-2976 Superconductors area unit among the foremost eccentric and material that are existing are nonetheless discovered.Quantum-mechanical effects mean that, below a essential temperature, they need zero resistivity. This property alone is quite enough to bring out the brillilant imagination. A current that would flow forever while not losing any energy suggests that transmission of power with nearly no losses within the cables. Once renewable energy sources begin to dominate the grid and high-voltage transmission across continents becomes vital to beat intermittence, lossless cables can lead to substantial savings. What’s a lot of, a superconducting wire carrying a current that ne'er, ever diminishes would act as an ideal store of power. in contrast to batteries, that degrade over time, if the resistance is actually zero, you'll come back to the superconductor during a billion years and realize that very same previous current flowing through it. Energy may well be captured and keep indefinitely! With no resistance, an enormous current may well be skilled in turn the wire that is superconducting,turn out magnetoic fields of unimaginable power.[14] CONCLUSION After reviewing on the topic superconductivity,we find that superconductivity can be new energy source for the whole mankind, even if superconductivity is discovered at the room temperature then there will be a new era of technology which will supress sources of energy such has hydro,bio-fuel and many more. ACKNOWLEDGMENTS It’s my pleasure to thank Mr. Amanparteek Singh and Rajiv Khullar sir for providing me constant support and suggestions. Their experience and advices were invaluable to my ability to make an accurate analysis. REFERENCE [1] John Bardeen; Leon Cooper; J. R. Schriffer (December one, 1957). "Theory of Superconductivity". Physical Review. 108 (5): 1175. Bibcode:1957PhRv..108.1175B. doi:10.1103/physrev.108.1175. ISBN 978-0-677-00080-0. Retrieved June half dozen, 2014. reprinted in Nikolaĭ Nikolaevich Bogoliubov (1963) the idea of electrical conduction, Vol. 4, CRC Press, ISBN 0677000804, p. 73 [2] John Daintith (2009). The Facts on File lexicon of Physics (4th erectile dysfunction.). Infobase commercial enterprise. p. 238. [3] John C. Gallop (1990). SQUIDS, the Josephson Effects and Superconducting natural philosophy. CRC Press. pp. 1, 20. [4] Durrant, Alan (2000). physical science of Matter. CRC Press. pp. 102–103. [5] H. K. Onnes (1911). "The resistance of pure mercury at He temperatures". Commun. Phys. Lab. Univ. Leiden. 12: 120. [6] Dirk vanDelft & Peter Kes (September 2010). "The Discovery of Superconductivity" (PDF). Physics these days. yankee Institute of Physics. sixty three (9): 38–43. Volume 8, Issue 3, 2018 46 https://pramanaresearch.org/ Pramana Research Journal ISSN NO: 2249-2976 [7] W. Meissner & R. Ochsenfeld (1933). "Ein neuer Effekt bei Eintritt der Supraleitfähigkeit". Naturwissenschaften. twenty one (44): 787–788. [8] F. London & H. London (1935). "The magnetism Equations of the Supraconductor". Proceedings of the honorary society of London
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