The London Equations Aria Yom Abstract: the London Equations Were the First Successful Attempt at Characterizing the Electrodynamic Behavior of Superconductors
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Technical Note 1
Gravito-Electromagnetic Properties of Superconductors - A Brief Review - C. J. de Matos1, M. Tajmar2 June 20th, 2003 Starting from the generalised London equations, which include a gravitomagnetic term, the gravitational and the electromagnetic properties of superconductors are derived. A phenomenological synthesis of those properties is proposed. Table of Contents I) Introduction................................................................................................2 II) Generalised London equations .................................................................2 II-a) Second generalised London equation .............................................3 II-b) First generalised London equation..................................................3 III) Gravito-electromagnetic properties of SCs .............................................3 III-a) Generalised Meissner effect ..........................................................4 III-b) SCs do not shield gravitomagnetic and / or gravitational fields....5 III-c) Generalised quantum fluxoid condition ........................................6 III-d) Supercurrents generated by GM fields..........................................7 III-e) Generalised London moment.........................................................8 III-f) Electric conductivity of SCs in a gravitational field......................9 III-g) Electrical fields in accelerated SCs .............................................13 IV) Conclusion.............................................................................................14 -
New Magnetosphere for the Earth in Future
WSEAS TRANSACTIONS on ENVIRONMENT and DEVELOPMENT Tara Ahmadi New Magnetosphere for the Earth In Future TARA AHMADI Student At Smart High School Kurdistan, Sanandaj, Ghazaly Street No3 IRAN [email protected] Abstract:- All of us know the earth magnetic field come to be less and this problem can be a serious problem in future but now we find other problems that can destroy our planet life or in minimum state can damage it such as FTE theory , solar activities , reversing magnetic poles, increasing speed of reversing that last reverse, reducing magnetic strength ,finding leaks in magnetosphere ,etc. some of these reasons will be factors for increasing the solar energy that hit to the Earth and perhaps changing in our life and conditions of the Earth . In this paper , I try to show a way to against to these problems and reduce their damages to the Earth perhaps The Earth will repair himself but this repair need many time that humans could not be wait. In the past time magnetic field was reversed but now we are against to the other problems that can increase the influence of reversing magnetic field for the Earth and all these events can be a separated problem for us, these problem may be can not destroyed humans life but can be cause of several problems that occur for our healthy and our technology in space. This way is building a system that produce a new magne tic field that will be in one way with old magnetic field this system will construe by superconductors and a metal that is not dipole. -
Electrodynamics of Superconductors Has to According to Maxwell’S Equations, Just As the Four-Vectors J a Be Describable by Relativistically Covariant Equations
Electrodynamics of superconductors J. E. Hirsch Department of Physics, University of California, San Diego La Jolla, CA 92093-0319 (Dated: December 30, 2003) An alternate set of equations to describe the electrodynamics of superconductors at a macroscopic level is proposed. These equations resemble equations originally proposed by the London brothers but later discarded by them. Unlike the conventional London equations the alternate equations are relativistically covariant, and they can be understood as arising from the ’rigidity’ of the superfluid wave function in a relativistically covariant microscopic theory. They predict that an internal ’spontaneous’ electric field exists in superconductors, and that externally applied electric fields, both longitudinal and transverse, are screened over a London penetration length, as magnetic fields are. The associated longitudinal dielectric function predicts a much steeper plasmon dispersion relation than the conventional theory, and a blue shift of the minimum plasmon frequency for small samples. It is argued that the conventional London equations lead to difficulties that are removed in the present theory, and that the proposed equations do not contradict any known experimental facts. Experimental tests are discussed. PACS numbers: I. INTRODUCTION these equations are not correct, and propose an alternate set of equations. It has been generally accepted that the electrodynam- There is ample experimental evidence in favor of Eq. ics of superconductors in the ’London limit’ (where the (1b), which leads to the Meissner effect. That equation response to electric and magnetic fields is local) is de- is in fact preserved in our alternative theory. However, scribed by the London equations[1, 2]. The first London we argue that there is no experimental evidence for Eq. -
Fritz London a Scientific Biography
Fritz London a scientific biography Kostas Gavroglu University of Athens, Greece CAMBRIDGE UNIVERSITY PRESS Contents Preface page xni Acknowledgements xxi 1 From philosophy to physics 1 The years that left nothing unaffected 2 The appeal of ideas 5 Goethe as a scientist 7 How absolute is our knowledge? 8 Acquiring knowledge 10 London's teachers in philosophy: Alexander Pfander and Erich Becher 11 Husserl's teachings 12 Abhorrence of reductionist schemata 14 The philosophy thesis 15 Tolman's principle of similitude 23 The necessary clarifications 25 Work on quantum theory 26 Transformation theory 28 Unsuccessful attempts at unification 31 2 The years in Berlin and the beginnings of quantum chemistry 38 The mysterious bond 39 London in Zurich 42 Binding forces 44 The Pauli exclusion principle 48 [ix] X FRITZ LONDON The early years in Berlin 49 Reactions to the Heitler—London paper 51 Polyelectronic molecules and the application of group theory to problems of chemical valence 53 Chemists as physicists? 57 London's first contacts in Berlin 59 Marriage 61 Job offers 64 Intermolecular forces 66 The book which could not be written 69 Leningrad and Rome 71 Difficulties with group theory 74 Linus Pauling's resonance structures 75 Robert Mulliken's molecular orbitals 78 Trying to save what could not be saved 82 3 Oxford and superconductivity 96 The rise of the Nazis 97 The changes at the University 102 Going to Oxford 105 Lindemann, Simon and Heinz London 106 Electricity in the very cold 110 The end of old certainties 113 The thermodynamic treatment -
Arxiv:0807.1883V2 [Cond-Mat.Soft] 29 Dec 2008 Asnmes 14.M 36.A 60.B 45.70.Mg 46.05.+B, 83.60.La, 81.40.Lm, Numbers: PACS Model
Granular Solid Hydrodynamics Yimin Jiang1, 2 and Mario Liu1 1Theoretische Physik, Universit¨at T¨ubingen,72076 T¨ubingen, Germany 2Central South University, Changsha 410083, China (Dated: October 27, 2018) Abstract Granular elasticity, an elasticity theory useful for calculating static stress distribution in gran- ular media, is generalized to the dynamic case by including the plastic contribution of the strain. A complete hydrodynamic theory is derived based on the hypothesis that granular medium turns transiently elastic when deformed. This theory includes both the true and the granular tempera- tures, and employs a free energy expression that encapsulates a full jamming phase diagram, in the space spanned by pressure, shear stress, density and granular temperature. For the special case of stationary granular temperatures, the derived hydrodynamic theory reduces to hypoplasticity, a state-of-the-art engineering model. PACS numbers: 81.40.Lm, 83.60.La, 46.05.+b, 45.70.Mg arXiv:0807.1883v2 [cond-mat.soft] 29 Dec 2008 1 Contents I. Introduction 3 II. Sand – a Transiently Elastic Medium 8 III. Jamming and Granular Equilibria 10 A. Liquid Equilibrium 10 B. Solid Equilibrium 11 C. Granular Equilibria 12 IV. Granular Temperature Tg 13 A. The Equilibrium Condition for Tg 13 B. The Equation of Motion for sg 14 C. Two Fluctuation-Dissipation Theorems 16 V. Elastic and Plastic Strain 17 VI. The Granular Free Energy 18 A. The Elastic Energy 20 B. Density Dependence of 22 B C. Higher-Order Strain Terms 23 D. Pressure Contribution From Agitated Grains 25 E. The Edwards Entropy 27 VII. Granular Hydrodynamic Theory 28 A. -
The Original Remark of Fritz London in 1938 ' Linking the Phenomenon of Superfluidity in He II with Boee-Einetein Con
IC/65A63 INTERNAL REPORT (Limited distribution) The original remark of Fritz London in 1938 ' linking the phenomenon of superfluidity in He II with Boee-Einetein con- •-International Atomic Energy Agency densation ( BEC ) has inspired a great deal of theory and ana experiment. On the other hand, the excitation spectrum was put I '!:-f. .Uni,ted^.Kati>ifis Educational Scientific and Cultural Organization on a solid microscopic basis by the remarkable variational 2 INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS calculation of Peynman and Cohen ( PC ), which connected the excitation Bpectrum with the dynamic structure factor obtained from inelastic neutron acatteringt and at the same BIOPHYSICS AND THE MICROSCOPIC THEORY OF He II * time pointed out the relevance of backflow. In spite of the importance of the FC variational calculation, which was later J. Chela-Florea ** improved upon by the Monte Carlo calculation of the excitation International Centre for Theoretical Physics, Trieste, Italy spectrum of He II, a few questions remain unanswered. Chief among these are: and (a) What ie the microscopic nature of He II? In particular, H.B. Ghassit what is the nature of the roton? Department of Physics, University of Jordan, Amman, Jordan (b) Are there any new excitations contributing to the disper- and International Centre for Theoretical Physics, Trieste, Italy sion relation? (c) How good is the PC wave function? (d) What is the connection between BEC and superfluidity? ABSTRACT The difficulty in obtaining completely satisfactory ans- Bose-Einstein condensation and solitonic propagation have recently wers to the above questions lieB partly in two experimental teen uhovn to be intimately related in "biosysteras. -
Some Analytical Solutions to Problems Using London Equations
Module 3 : Superconductivity phenomenon Lecture 2 : Solution of London equations and free energy calculations Solution of London Equations for sample cases Flat slab in a magnetic field Consider a flat superconducting slab of thickness in a magnetic field parallel to the slab. The boundary condition is that field match at . Subject to this condition, the solution to the London equation , where is the microscopic value of the flux density, is easily determined to be a superposition of two exponentials. The result can be written as (13) Clearly, the minimum value of the flux density is attained at the mid-plane of the slab where it has a value . The field variation inside a superconducting slab is shown. Averaging this internal field over the sample thickness one gets (14) Let us consider the limit . This leads to deep inside the superconductor. In the other limit, i.e., , we expand . Therefore, approaches . Since , we get (15) As a consequence, magnetisation measurements can be made on thin films of known thicknesses and the penetration depth can be estimated from such measurements. Since the magnetisation is reduced below its Meissner value, the effective critical field for a thin sample is greater than that for bulk. The difference in the free energy between the normal state and the superconducting state is (16) For the case of complete flux expulsion, the above difference in free energies is (17) This energy, which stabilises the superconducting state is called the condensation energy and is called the thermodynamic critical field. For a thin film sample (with a field applied parallel to the plane) we get, (18) In terms of the bulk thermodynamic critical field (19) Critical current of a wire Consider a long superconducting wire having a circular cross-section of radius . -
Non-Local Electrodynamics of Superconducting Wires: Implications for Flux Noise and Inductance
Non-Local Electrodynamics of Superconducting Wires: Implications for Flux Noise and Inductance by Pramodh Viduranga Senarath Yapa Arachchige B.Sc., Carleton University, 2015 A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in the Department of Physics and Astronomy c Pramodh Viduranga Senarath Yapa Arachchige, 2017 University of Victoria All rights reserved. This thesis may not be reproduced in whole or in part, by photocopying or other means, without the permission of the author. ii Non-Local Electrodynamics of Superconducting Wires: Implications for Flux Noise and Inductance by Pramodh Viduranga Senarath Yapa Arachchige B.Sc., Carleton University, 2015 Supervisory Committee Dr. Rog´eriode Sousa, Supervisor (Department of Physics and Astronomy) Dr. Reuven Gordon, Outside Member (Department of Electrical and Computer Engineering) iii Supervisory Committee Dr. Rog´eriode Sousa, Supervisor (Department of Physics and Astronomy) Dr. Reuven Gordon, Outside Member (Department of Electrical and Computer Engineering) ABSTRACT The simplest model for superconductor electrodynamics are the London equations, which treats the impact of electromagnetic fields on the current density as a localized phenomenon. However, the charge carriers of superconductivity are quantum me- chanical objects, and their wavefunctions are delocalized within the superconductor, leading to non-local effects. The Pippard equation is the generalization of London electrodynamics which incorporates this intrinsic non-locality through the introduc- tion of a new superconducting characteristic length, ξ0, called the Pippard coherence length. When building nano-scale superconducting devices, the inclusion of the coher- ence length into electrodynamics calculations becomes paramount. In this thesis, we provide numerical calculations of various electrodynamic quantities of interest in the non-local regime, and discuss their implications for building superconducting devices. -
50 Years of BCS Theory “A Family Tree” Ancestors BCS Descendants
APS March Meeting 2007 50 Years of BCS Theory “A Family Tree” Ancestors BCS Descendants D. Scalapino: Ancestors and BCS J. Rowell : A “tunneling” branch of the family G. Baym: From Atoms and Nuclei to the Cosmos Supraconductivity 1911 H. Kamerlingh Onnes `(Gilles Holst) finds a sudden drop in the resistance of Hg at ~ 4.2K. R(ohms) T 1933 Meissner and Ochsenfeld discover that superconductors are perfect diamagnets --flux expulsion Robert Ochsenfeld 1901 - 1993 Phenomenolog` y • 1934 Casimir and Gorter ‘s two-fluid phenomenological model of thermodynamic properties. • 1934 Heinz and Fritz London’s phenomenological electrodynamics. F. London’s suggestion of the rigidity of the wave function. • 1948 Fritz London, “Quantum mechanics on a macroscopic scale, long range order in momentum.” Fritz London (1900-1954) 1950 Ginzburg-Landau Theory n∗ ! e∗ β f(x) = Ψ(x) + A(x)Ψ(x) 2 + α Ψ(x) 2 + Ψ(x) 4 2m∗ | i ∇ c | | | 2 | | β +α Ψ(x) 2 + Ψ(x) 4 | | 2 | | V. Ginzburg L. Landau 1957 Type II Superconductivity Aleksei Abrikosov But the question remained: “How does it work?” R.P. Feynman ,1956 Seattle Conference But the question remained: “How does it work?” A long list of the leading theoretical physicists in the world had taken up the challenge of developing a microscopic theory of superconductivity. A.Einstein,“Theoretische Bemerkungen zur Supraleitung der Metalle” Gedenkboek Kamerlingh Onnes, p.435 ( 1922 ) translated by B. Schmekel cond-mat/050731 “...metallic conduction is caused by atoms exchanging their peripheral electrons. It seems unavoidable that supercurrents are carried by closed chains of molecules” “Given our ignorance of quantum mechanics of composite systems, we are far away from being able to convert these vague ideas into a theory.” Felix Bloch is said to have joked that ”superconductivity is impossible”. -
Ultra-Low Temperature Measurements of London Penetration Depth in Iron Selenide Telluride Superconductors
University of New Orleans ScholarWorks@UNO University of New Orleans Theses and Dissertations Dissertations and Theses Fall 12-20-2013 Ultra-low Temperature Measurements of London Penetration Depth in Iron Selenide Telluride Superconductors Andrei Diaconu University of New Orleans, [email protected] Follow this and additional works at: https://scholarworks.uno.edu/td Part of the Condensed Matter Physics Commons Recommended Citation Diaconu, Andrei, "Ultra-low Temperature Measurements of London Penetration Depth in Iron Selenide Telluride Superconductors" (2013). University of New Orleans Theses and Dissertations. 1731. https://scholarworks.uno.edu/td/1731 This Dissertation is protected by copyright and/or related rights. It has been brought to you by ScholarWorks@UNO with permission from the rights-holder(s). You are free to use this Dissertation in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Dissertation has been accepted for inclusion in University of New Orleans Theses and Dissertations by an authorized administrator of ScholarWorks@UNO. For more information, please contact [email protected]. Ultra-low Temperature Measurements of London Penetration Depth in Iron Selenide Telluride Superconductors A Dissertation Submitted to the Graduate Faculty of the University of New Orleans in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering and Applied Science Physics by Andrei Diaconu B.S. “Alexandru Ioan Cuza” University, Iasi, Romania, 2006 M.S. -
MARTIN J. KLEIN June 25, 1924–March 28, 2009
NATIONAL ACADEMY OF SCIENCES M ARTIN J. KLEIN 1 9 2 4 – 2 0 0 9 A Biographical Memoir by DIANA K O R M O S - B U CHW ALD AND JED Z . B U C HW ALD Any opinions expressed in this memoir are those of the authors and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2011 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. MARTIN J. KLEIN June 25, 1924–March 28, 2009 BY DIANA K O R M O S - B U CHWALD AND J ED Z . B UCHW ALD ARTIN JESSE KLEIN, PHYSICIST AND HISTORIAN, died on March M28, 2009, at his home in Chapel Hill, North Carolina. Known to many as “Marty,” Klein was among the foremost historians of science worldwide, a beloved teacher, colleague, and friend, who in his many writings in the history of physics set an unparalleled model of deep, critical, and empathetic understanding of science and scientists. Klein was born on June 25, 1924, in New York City, the only child of Adolph and Mary Klein, both schoolteachers. At age 14, Klein graduated from the James Monroe High School in the South Bronx, where he had struck up a lifelong, close friendship with Leon M. Lederman. Both became students at Columbia University, from which Klein graduated with a bachelor’s degree in mathematics in 1942 and a master’s degree in physics in 1944. “He was way younger than me; it was embarrassing,” Lederman remembered. “He won most of the awards at graduation: the chemistry prize, the history prize, English composition. -
Physical Processes in Disordered Superconductors
COMENIUS UNIVERSITY IN BRATISLAVA FACULTY OF MATHEMATICS, PHYSICS AND INFORMATICS Physical processes in disordered superconductors 2016 RNDr. Martin Zemliˇckaˇ COMENIUS UNIVERSITY IN BRATISLAVA FACULTY OF MATHEMATICS, PHYSICS AND INFORMATICS Physical processes in disordered superconductors Dissertation thesis 4.1.3 Condensed matter physics and acoustics Department of experimental physics Bratislava, 2016 RNDr. Martin Zemliˇckaˇ 51249511 Comenius University in Bratislava Faculty of Mathematics, Physics and Informatics THESIS ASSIGNMENT Name and Surname: Mgr. Martin Žemlička Study programme: Condense Matter Physics and Acoustics (Single degree study, Ph.D. III. deg., full time form) Field of Study: Physics Of Condensed Matter And Acoustics Type of Thesis: Dissertation thesis Language of Thesis: English Secondary language: Slovak Title: Physical processes in disordered superconductors. Literature: 1. A Tholen, Parametric amplification with weak-link nonlinearity in superconducting microresonators, arXiv:0906.2744v2 2.G. Wendin, V.S. Shumeiko,Superconducting Quantum Circuits, Qubits and Computing arXiv:cond-mat/0508729v1 3. A. M. ZAGOSKIN, QUANTUM ENGINEERING, Cambridge University Press 2011 4. L. Skrbek a kol. Fyzika nízkých teplot, matfyzpress PRAHA 2011 Aim: The aim of the thesis is the examination of physical processes in disordered superconductors and nonlinear effects in superconducting nanostructures. Such structures can be applied as very sensitive detectors usable in astronomy, experimental physics or in quantum information processing. Tutor: doc. RNDr. Miroslav Grajcar, DrSc. Department: FMFI.KEF - Department of Experimental Physics Head of prof. Dr. Štefan Matejčík, DrSc. department: Assigned: 01.09.2012 Approved: 01.03.2012 prof. RNDr. Peter Kúš, DrSc. Guarantor of Study Programme Student Tutor 51249511 Univerzita Komenského v Bratislave Fakulta matematiky, fyziky a informatiky ZADANIE ZÁVEREČNEJ PRÁCE Meno a priezvisko študenta: Mgr.