超导物理 义PPT课件

课程介绍n参考书:1)张裕恒：超导物理，中国科技大学出版社2)章立源等：超导物理学，电子工业出版社3)张其瑞：高温超导电性，浙江大学出版社4)M. Tinkham: “Introduction to Superconductivity”, McGraw-Hill, Inc.n考试等：2008-9-111第1页/共48页OutlinenDiscovery of SuperconductivitynDevelopment of Superconducting MaterialsnBasic Properties of SuperconductorsnPhenomenological TheoriesnMicroscopic TheoriesnNew Challenges (HTSC)2008-9-112第2页/共48页Discovery of Superconductivityn19th Century: Down to lower TnFirst to liquefy “the permanent gas” HeliumnPt: residual resistance is related to the impuritynMercury is easy to purifiednDiscovery of SC in Hg in 19112008-9-113第3页/共48页Discovery of SuperconductivityH. K. Onnes, Commun. Phys. Lab.12,120, (1911)Zero Electrical ResistanceMeasurement vs. Observation2008-9-114第4页/共48页Zero resistance, Really?52008-9-11第5页/共48页2008-9-116第6页/共48页2008-9-117第7页/共48页2008-9-118第8页/共48页Discovery of SuperconductivityMeissner EffectIdeal ConductorSuperconductorMagnetic levitation“Flux frozen”2008-9-119第9页/共48页2008-9-1110第10页/共48页112008-9-11第11页/共48页122008-9-11第12页/共48页2008-9-1113第13页/共48页Superconductivity is not rarenElementsnAlloysnInorganic compoundsnOrganic compoundsnPolymersnBiosystems?2008-9-1114第14页/共48页2008-9-1115第15页/共48页Superconducting Critical Magnetic Field2008-9-1116第16页/共48页172008-9-11Definition of Tc, Hc and Jc第17页/共48页Type I and Type II Superconductors2008-9-1118第18页/共48页Vortex State for Type II Superconductors2008-9-1119第19页/共48页202008-9-11第20页/共48页Vortex Pinning for Type II SuperconductorsTo induce defects to pin the vortices: Increasing Jc; Superconducting magnet2008-9-1121第21页/共48页Theoretical prediction of vortices in type II superconductorsFirst published in 1952 2008-9-1122第22页/共48页2003 Nobel Laureates for PhysicsAlexei A. Abrikosov Vitaly L. Ginzburg Anthony J. Leggett USA and Russia Russia United Kingdom and USA 2008-9-1123第23页/共48页Theory of SuperconductivitynPhenomenological Theory London Theory Ginzberg-Landau-Abricosov-Gorkov TheorynMicroscopic Theory BCS Theory Other TheoriesMacroscopic Quantum Phenomenon =(r)=Aei(r)2008-9-1124第24页/共48页BCS Theory of Superconductivity2008-9-1125第25页/共48页超导机制超导机制Cooper电子对电子对实空间实空间正常态正常态超导态超导态动量空间动量空间2008-9-1126第26页/共48页BCS Theory of Superconductivityn1972 Nobel Prize for PhysicsJohn Bardeen Leon Neil Cooper John Robert Schrieffer 2008-9-1127第27页/共48页Josephson Effectn1973 Nobel Prize for PhysicsCompleted the great work as a postgraduate!2008-9-1128第28页/共48页Superconducting quantum interference device (SQUID) nThreshold for SQUID: 10-14 TnMagnetic field of heart:10-10 TnMagnetic field of brain: 10-13 T2008-9-1129第29页/共48页Discovery of HTSCnBackground Theory: Little, Ginzberg, Experiments:nOxides, the ceramic superconductors Ba(Pb,Bi)O3; LixTi2O4n(La,Ba)2CuO42008-9-1130第30页/共48页Discovery of HTSCBednorz and Muller, Z. Physik B64, 189, (1986)2008-9-1131第31页/共48页Discovery of HTSCfor their important break-through in the discovery of superconductivity in ceramic materials K. Alexander Muller J. Georg Bednorzn1987 Nobel Prize for Physics2008-9-1132第32页/共48页Retrospection on the Discovery of HTSCn(La,Ba)2CuO4: A French Group (B. Raveau) A Russian GroupnPioneer Proposal on Oxide Superconductor in China: Ba(Pb,Bi)O3nNew discovery and its impact on Science & Technology2008-9-1133第33页/共48页Common structure model of HTSC2008-9-1134第34页/共48页2008-9-1135第35页/共48页Electronic Phase Diagram of HTSC2008-9-1136第36页/共48页Superconducting Gap Functions(0,)(,0)(/2,/2)s-wave gapd-wave gap2008-9-1137第37页/共48页赝能隙现象与预超导配对 传统超导体传统超导体 Cooper对的出现与建立相干性同步完成. 一般单电子高温超导体高温超导体Tc一般单电子Cooper PairsBose-Einstein CondensationT*Tc涨落的Cooper对相干的Cooper对：BEC2008-9-1138第38页/共48页2008-9-1139第39页/共48页nIs average field theory enough to elucidate HTSC?nNanoscale phase separations: key to the high-Tc?nThe Role of Quenched Disorder?2008-9-1140第40页/共48页2022-5-21New High-Tc SuperconductorsLaFeAsO, 1111, 56 KBaFe2As2, 122, 38 K第41页/共48页2022-5-21第42页/共48页2022-5-21111, LiFeAs, 18 K11, FeSe, 10 K第43页/共48页2022-5-21Building Blocks第44页/共48页Mechanism of HTSC?揭示高温超导机理 = 诺贝尔物理学奖发现室温超导体= 诺贝尔物理学奖2008-9-1145第45页/共48页Nobel Prizes mark MILESTONES in the area of SUPERCONDUCTIVITYn1911 Discovery of superconductivity n1950-1957: GLAG Theory n1957 BCS Theoryn1962 Josephson Effectn1986 A. Mller and G. Bednorz: discovery of HTSCn? 2008-9-1146第46页/共48页思考题、调研题与习题n1. 论述理想导体与超导体之差别。n2. 目前为止，超导现象出现在哪些系统中？你认为未来的“新超导体”可能在哪些系统中被发现？n3. 超导研究的里程碑式的工作有哪些？n4. 调研“关于超导的应用”。472008-9-11第47页/共48页482008-9-11感感谢您谢您的的观观看。看。第48页/共48页