超导物理 第一讲 讲义

John Bardeen
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Leon Neil Cooper
John Robert Schrieffer
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Josephson Effect

1973 Nobel Prize for Physics
Completed the great work as a postgraduate!
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Nobel Prizes mark MILESTONES in the area of SUPERCONDUCTIVITY
1911 Discovery of superconductivity 1950-1957: GLAG Theory 1957 BCS Theory 1962 Josephson Effect 1986 A. Mü ller and G. Bednorz: discovery of HTSC ????
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Superconducting Critical Magnetic Field
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Definition of Tc, Hc and Jc
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Type I and Type II Superconductors
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LaFeAsO, 1111, 56 K
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BaFe2As2, 122, 38 K
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111, LiFeAs, 18 K
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11, FeSe, 10 K
Building Blocks
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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
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Superconducting quantum interference device (SQUID)

Threshold for SQUID: 10-14 T Magnetic field of heart:10-10 T Magnetic field of brain: 10-13 T
Superconductor
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Superconductivity is not rare



Elements Alloys Inorganic compounds Organic compounds Polymers Biosystems?
Vitaly L. Ginzburg Russia
Anthony J. Leggett United Kingdom and USA
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Theory of Superconductivity
Phenomenological Theory London Theory Ginzberg-Landau-Abricosov-Gorkov Theory Microscopic Theory BCS Theory Other Theories Macroscopic Quantum Phenomenon
K. Alexander Muller
J. Georg Bednorz
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Retrospection on the Discovery of HTSC

(La,Ba)2CuO4: A French Group (B. Raveau) A Russian Group Pioneer Proposal on Oxide Superconductor in China: Ba(Pb,Bi)O3 New discovery and its impact on Science & Technology
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Zero resistance, Really?
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9wk.baidu.com
Discovery of Superconductivity
Meissner Effect
Ideal Conductor “Flux frozen” Magnetic levitation
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赝能隙现象与预超导配对
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
一般单电子
T*
涨落的Cooper对
Tc
Cooper Pairs Bose-Einstein Condensation
Tc
相干的Cooper对： BEC
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Is average field theory enough to elucidate HTSC? Nanoscale phase separations: key to the high-Tc? The Role of Quenched Disorder?


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New High-Tc Superconductors
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Theoretical prediction of vortices in type II superconductors
First published in 1952
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2003 Nobel Laureates for Physics
Alexei A. Abrikosov USA and Russia

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Discovery of HTSC
Bednorz and Muller, Z. Physik B64, 189, (1986)
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Discovery of HTSC

1987 Nobel Prize for Physics "for their important break-through in the discovery of superconductivity in ceramic materials"
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Discovery of Superconductivity
Zero Electrical Resistance
H. K. Onnes, Commun. Phys. Lab.12,120, (1911)
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思考题、调研题与习题
1. 论述理想导体与超导体之差别。 2. 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？ 3. 超导研究的里程碑式的工作有哪些？ 4. 调研“关于超导的应用”。

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Outline


Discovery of Superconductivity Development of Superconducting Materials Basic Properties of Superconductors Phenomenological Theories Microscopic Theories New Challenges (HTSC)


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Common structure model of HTSC
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Electronic Phase Diagram of HTSC
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Superconducting Gap Functions
s-wave gap d-wave gap (0,) (/2,/2) (,0)
“超导物理”第一讲
Overview of Superconductivity
浙江大学凝聚态物理研究所CGH
课程介绍
1) 2) 3) 4)
参考书: 张裕恒：《超导物理》，中国科技大学出版社 章立源等：《超导物理学》，电子工业出版社 张其瑞：《高温超导电性》，浙江大学出版社 M. Tinkham: “Introduction to Superconductivity”, McGraw-Hill, Inc. 考试等：
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Vortex State for Type II Superconductors
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Vortex Pinning for Type II Superconductors
To induce defects to pin the vortices: Increasing Jc; Superconducting magnet
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Discovery of Superconductivity



19th Century: Down to lower T First to liquefy “the permanent gas” Helium Pt: residual resistance is related to the impurity Mercury is easy to purified Discovery of SC in Hg in 1911
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Discovery of HTSC
Background Theory: Little, Ginzberg, … Experiments: Oxides, the ceramic superconductors Ba(Pb,Bi)O3; LixTi2O4 (La,Ba)2CuO4

=(r)=Aei(r)
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BCS Theory of Superconductivity
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超导机制－Cooper电子对
动量空间 实空间
正常态
超导态
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BCS Theory of Superconductivity

1972 Nobel Prize for Physics