Oxford handbook of small superconductors

641 Pages·2017·33.046 MB·English

by  Narlikar, A. V

i
THE OXFORD HANDBOOK
OF SMALL SUPERCONDUCTORS
ii
iii
The Oxford Handbook
of Small Superconductors
Edited by
A.V. Narlikar
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1
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Contents
Plan of the Book and Acknowledgments xi
List of Contributors xvii
Part I Introduction and Basic Studies
1 Small Superconductors— Introduction 3
A.V. Narlikar
1.1 Two characteristic length scales of superconductors 3
1.2 Two size effects in superconductors 8
1.3 QSE, quantum fluctuations, Anderson limit, parity and shell effects, etc. 9
1.4 Factors influencing small size effects 12
1.5 Behavior of nanowires and ultra- thin films 16
1.6 Vortex states of small superconductors 20
1.7 Proximity effect behaviors 25
1.8 Synthesis of small superconductors 28
1.9 Summary and outlook 33
2 Local- Scale Spectroscopic Studies of Vortex Organization in Mesoscopic Superconductors 40
D. Roditchev, T. Cren, C. Brun, and M. Miloševic
2.1 Basic properties of quantum vortices in superconductors 41
2.2 Experimental requirements for studying vortex confinement phenomena 51
2.3 Observation of confinement effects on vortices 54
2.4 Conclusions and outlook 76
3 Multi- Vortex States in Mesoscopic Superconductors 81
N. Kokubo, S. Okayasu, and K. Kadowaki
3.1 Introduction 81
3.2 Magnetic imaging of superconducting vortices 83
3.3 Observation of multi- vortex states in mesoscopic superconductors 87
3.4 Summary and outlook 103
4 Proximity Effect: A New Insight from In Situ Fabricated Hybrid Nanostructures 108
J.C. Cuevas, D. Roditchev, T. Cren, and C. Brun
4.1 An introduction to proximity effect 109
4.2 In situ fabricated hybrid nanostructures and tunneling spectroscopy 123
4.3 Proximity effect in a correlated 2D disordered metal 126
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4.4 Proximity effect in diffusive SNS junctions 129
4.5 Proximity Josephson vortices 131
4.6 Proximity effect between two different superconductors 135
4.7 Conclusions and outlook 139
5 Andreev Reflection and Related Studies in Low- Dimensional Superconducting Systems 144
D. Daghero, G.A. Ummarino, and R.S. Gonnelli
5.1 Basics of point- contact Andreev- reflection spectroscopy 145
5.2 Andreev reflection in a nutshell 150
5.3 Length scales in mesoscopic systems 155
5.4 Examples of PCARS in superconductors with reduced dimensionality 165
5.5 Summary and outlook 177
6 Topological Superconductors and Majorana Fermions 183
Y.Y. Li and J.F. Jia
6.1 Introduction 183
6.2 TI/ SC heterostructures 185
6.3 Nanowire/ SC junctions 195
6.4 FM atomic chain on SCs 199
6.5 Summary and outlook 202
7 Surface and Interface Superconductivity 207
S. Gariglio, M.S. Scheurer, J. Schmalian, A.M.R.V.L. Monteiro, S. Goswami, and A.D. Caviglia
7.1 Introduction 207
7.2 Superconductivity in two dimensions 208
7.3 Superconductivity in ultra-t hin metals on Si(111) 210
7.4 Superconductivity at the LaAlO / SrTiO interface 215
3 3
7.5 Summary and outlook 231
Part II Materials Aspects
8 Mesoscopic Effects in Superconductor– Ferromagnet Hybrids 241
G. Karapetrov, S.A. Moore, and M. Iavarone
8.1 Theories underpinning S/ F hybrid structures 242
8.2 Domain wall and reverse domain superconductivity 249
8.3 Vortex behavior in planar S/ F hybrids 256
8.4 Conclusions and outlook 261
9 Theoretical Study of THz Emission from HTS Cuprate 265
H. Asai
9.1 Intrinsic Josephson junction (IJJ) in HTS cuprate 266
9.2 THz emitter utilizing IJJs 271
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Contents vii
9.3 Temperature inhomogeneity in IJJ- based THz emitter 273
9.4 THz emission from IJJs with temperature inhomogeneity 274
9.5 Summary 286
10 Micromagnetic Measurements on Electrochemically Grown Mesoscopic Superconductors 291
A. Müller, S.E.C. Dale, and M.A. Engbarth
10.1 Introduction 291
10.2 Electrochemical preparation of β- tin samples 296
10.3 Measurement techniques and sample preparation 300
10.4 Summary and outlook 317
11 Growth and Characterization of HTSc Nanowires and Nanoribbons 321
M.R. Koblischka
11.1 HTSc nanowires prepared by the template method 321
11.2 HTSc nanowires prepared by electrospinning 326
11.3 Use of HTSc nanowires as building blocks 341
11.4 Summary and outlook 342
12 Mesoscopic Structures and Their Effects on High-T Superconductivity 347
c
H. Zhang
12.1 Introduction and motivation 348
12.2 Model 350
12.3 Calculating results and discussion 352
12.4 Strain between two blocks and its effect on superconductivity 356
12.5 Carrier- compensated system and mesoscopic structures 359
12.6 Existence of fixed triangle (local mesoscopic structure) by x- ray diffraction 363
12.7 The existence of the fixed triangle (local mesoscopic structure) demonstrated
by Raman spectroscopy 365
12.8 Low wave number evidence about mesoscopic structure 368
12.9 Discussions 369
12.10 Summary and outlook 375
13 Magnetic Flux Avalanches in Superconducting Films with Mesoscopic Artificial Patterns 379
M. Motta, A.V. Silhanek, and W.A. Ortiz
13.1 Avalanches in superconductors 380
13.2 Artificial pinning centers in superconducting films 391
13.3 Effects of the antidot geometry and lattice symmetry in flux avalanches 399
13.4 Summary and outlook 406
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Part III Device Technology
14 Superconducting Spintronics and Devices 415
M.G. Blamire and J.W.A. Robinson
14.1 Conventional spintronics 416
14.2 The rationale for superconducting spintronics 417
14.3 S/ F proximity effects and Josephson junctions 418
14.4 Spin transport in the superconducting state 421
14.5 Superconducting spintronic memory 423
14.6 Superconducting spintronic logic 424
14.7 Superconductor/ ferromagnet thermoelectric devices 424
14.8 Materials and device structures 425
14.9 Summary and outlook 427
15 Barriers in Josephson Junctions: An Overview 432
M.P. Weides
15.1 Josephson effect 433
15.2 Tunnel barriers 443
15.3 Metallic barriers 449
15.4 Semiconducting barriers 450
15.5 Magnetic barriers 451
15.6 Summary and outlook 453
16 Hybrid Superconducting Devices Based on Quantum Wires 459
K. Grove-R asmussen, T.S. Jespersen, A. Jellinggaard, and J. Nygård
16.1 Introduction 459
16.2 Experimental aspects of hybrid devices 460
16.3 Superconducting junctions with normal quantum dots 463
16.4 Superconductivity- enhanced spectroscopy of quantum dots 467
16.5 Sub- gap states in hybrid quantum dots 468
16.6 Non- local signals in hybrid double quantum dots 472
16.7 Epitaxial superconducting contacts to nanowires 477
16.8 Summary and outlook 482
17 Superconducting Nanodevices 492
J. Gallop and L. Hao
17.1 The drive to the nanoscale 492
17.2 Types of Josephson junction 494
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17.3 NanoSQUIDs imply improved energy sensitivity 503
17.4 Applications 506
17.5 Future developments 516
17.6 Summary and outlook 520
18 Superconducting Quantum Bits of Information—C oherence and Design Improvements 524
J. Bylander
18.1 Introduction: superconducting qubits 524
18.2 Single-q ubit Hamiltonians and reference frames 526
18.3 Decoherence. Characterization and mitigation of noise 529
18.4 Superconducting qubits 539
18.5 Circuit quantum electrodynamics (c- QED) 553
18.6 Second- generation superconducting qubits 557
18.7 Summary and outlook 561
19 NanoSQUIDs Applied to the Investigation of Small Magnetic Systems 567
M. J. Martínez- Pérez, R. Kleiner, and D. Koelle
19.1 SQUID basics 567
19.2 NanoSQUIDs 572
19.3 Measurement techniques using nanoSQUIDs 590
19.4 Particle positioning 592
19.5 Applications 596
19.6 Summary and outlook 600
Index 607