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R. G
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, A. M
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Wal
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Intro - 1
Applied Superconductivity
Josephson Effects, Superconducting Electronics,
and Quantum Circuits
Lecturer: Frank [email protected]
Lecture NotesSummer Semester 2013
R. Gross and F. Deppe© Walther-Meißner-Institut
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Intro - 2
The following lectures are offered on a regular basis:
1. Superconductivity and Low Temperature Physics I (WS) Foundations of Superconductivity
2. Superconductivity and Low Temperature Physics II (Thursday 12:30h, HS 3) Foundations of Low Temperature Physics and Techniques
3. Applied Superconductivity (this lecture!) Josephson-Effects, Superconducting Electronics, Quantum Circuits
4. Several Seminars (see announcements)
Documents and Hints (download):http://www.wmi.badw.de Teaching Lecture notesdownload available lecture notes and slides
Superconducting Quantum CircuitsTue. 14:30 – 16:00hLibrary, WMI
Advances in Solid-State PhysicsTue. 10:15 – 11:30hSeminar room 143, WMI
General Remarks on the Courses to the Field
“Superconductivity and Low Temperature Physics”
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Intro - 5
I Foundations of the Josephson Effect
1 Macroscopic Quantum Phenomena1.1 The Macroscopic Quantum Model of Superconductivity1.2 Fluxoid/Flux Quantization1.3 Josephson Effect
2 JJs: The Zero Voltage State 2.1 Basic Properties of Lumped Josephson2.2 Short Josephson Junctions2.3 Long Josephson Junctions
3 JJs: The Voltage State 3.1 The Basic Equation of the Lumped Josephson Junction3.2 The Resistively and Capacitively Shunted Junction Model3.3 Response to Driving Sources3.4 Additional Topic: Effect of Thermal Fluctuations3.5 Secondary Quantum Macroscopic Effects3.6 Voltage State of Extended Josephson Junctions
Contents of Lecture
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Intro - 6
II Applications of the Josephson Effect
4 SQUIDs
4.1 The dc-SQUID4.2 The rf-SQUID4.3 Additional Topic: Other SQUID Configurations4.4 Instruments Based on SQUIDs4.5 Applications of SQUIDs
5 Digital Electronics
5.1 Superconductivity and Digital Electronics5.2 Voltage State Josephson Logic5.3 RSFQ Logic5.4 Analog-to-Digital Converters
6 The Josephson Voltage Standard
6.1 Voltage Standards6.2 The Josephson Voltage Standard6.3 Programmable Josephson Voltage Standard
Contents of Lecture
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Intro - 7
7 Superconducting Photon and Particle Detectors
7.1 Superconducting Microwave Detectors: Heterodyne7.2 Superconducting Microwave Detectors: Direct Detectors7.3 Thermal Detectors7.4 Superconducting Particle and Single Photon Detectors7.5 Other Detectors
8 Microwave Applications
8.1 High Frequency Properties of Superconductors8.2 Superconducting Resonators and Filters8.3 Superconducting Microwave Sources
Contents of Lecture
R. G
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Intro - 8
III Superconducting Quantum Circuits
10 Superconducting Quantum Circuits
10.0 Quantum treatment of Josephson junctions10.1 Superconducting quantum circuits10.2 Introduction to quantum information processing10.3 Control of quantum two-level systems10.4 Physics of superconducting quantum circuits10.5 Circuit quantum electrodynamics
Contents of Lecture
R. G
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Intro - 9
Werner Buckel, Reinhold Kleiner, Supraleitung – Grundlagen und AnwendungenVCH-Verlag, Weinheim (2012).
R. Gross, A. MarxFestkörperphysik, Oldenbourg-Verlag (2012).
M. Tinkham, Introduction to SuperconductivityMcGraw-Hill, New York (1975).
K. K. Likharev, Dynamics of Josephson Junctions and CircuitsGordon and Breach Science Publishers, New York (1986).
T. P. Orlando, K. A. Delin, Foundations of Applied SuperconductivityAddison-Wesley, New York (1991).
Lecture notes & slides: R. Gross, A. Marx, http://www.wmi.badw.de/teaching/Lecturenotes/index.html
M. A. Nielsen, I. L. ChuangQuantum Computation and Quantum InformationCambridge University Press
D. E. Walls, G. J. MilburnQuantum Optics2nd edition, Springer
Bibliography
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Intro - 10
Introduction
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Intro - 11
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
106
107
108
109
tem
per
atu
re (
K)
same amount of new physicson every decade of log T scale
center of hottest stars
center of the sun, nuclear energies
electronic energies, chemical bonding
surface of sun, highest boiling temperatures
organic life
liquid air
liquid 4Heuniverse
superfluid 3He
lowest temperatures of condensed matter
elec
tro
nic
m
ag
net
ism
nu
clea
r-m
ag
net
ism
sup
erco
nd
uct
ivit
y
low
te
mp
era
ture
re
se
arc
h
lowest temperature in nuclear spin system achieved by adiabatic demagnetizationof Rhodium nuclei: ≈ 100 pK
Temperature scale
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Intro - 13
path dependentfinal state of theperfect conductor
perfect conductor in magnetic field
increase Bext
increase
Bext
decrease T
decrease T
C
C PC
PCPC
conductor
perfectconductor PC
PC
switch off Bext
Perfect conductor in magnetic field
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Intro - 14
perfect diamagnetism
Walther Meißner(1882 – 1974)
Robert Ochsenfeld(1901 – 1993)
W. Meißner, R. Ochsenfeld, Ein neuer Effekt bei Eintritt der Supraleitfähigkeit, Naturwissenschaften 21, 787 (1933).
Discovery of the Meißner-Ochsenfeld Effect (1933)
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Intro - 15
Carl Paul Gottfried von Linde* 11. Juni 1842 in Berndorf, Oberfranken
† 16. November 1934 in Munich
1868 offer of chair at thePolytechnische Schule München (now TUM)
1873 development of cooling machine allowingthe temperature stabilization in beer brewing
21. 6. 1879 foundation of „Gesellschaft für Linde’sEismaschinen AG“ together with twobeer brewers and three other co-founders
1892 - 1910 re-establishment of professorship
12.5.1903 patent application: „Lindesches Gegenstrom-verfahren“liquefaction of oxygen(-182°C = 90 K)
Low Temperature Technology in Germany
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Intro - 16
• Helium liquefaction: 1908• discovery of superconductivity: 1911 H. K. Onnes, Comm. Leiden 120b (1911)
Nobel Price in Physics 1913
choice of name:
infinite electrical conductivity
He
ike
Kam
me
rlin
ghO
nn
es
(18
53
-19
26
)
superconductivity
Universität Leiden (1911)
Tc = - 269°C
Hg
Temperatur (K)W
ider
stan
d
(W)
<
"for his investigations on the properties of matter atlow temperatures which led, inter alia to theproduction of liquid helium"
Discovery of Superconductivity (1911)
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Intro - 18
Discovery of Superconductivity (1911)
Kammerlingh Onnes and van der Waals
Kammerlingh Onnes and technician Flim
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Intro - 19
Wa
lth
er M
eiß
ner
(1
88
2 –
19
74
)
superconductors perfectly expel magnetic field
ideal diamagnetism, c = – 1
0 1 exin BB c
choice of name for perfect diamagnetism:
Meißner-Ochsenfeld Effect
superconductor
T > TC T < TC
B B
(c = magneticsusceptibility)
Discovery of the Meißner-Ochsenfeld Effect (1933)
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Intro - 20
superconductor in magnetic field
Meißner-Ochsenfeld-Effect
or
perfect diamagnetism
super-conductor
C
C
SCSC
SC
increase
Bext
decrease T
increase Bext
decrease T
switch off Bext
SC
SCconductor
path independentfinal state of thesuperconductor
superconducting state is a
thermodynamic phase
Superconductor in magnetic field
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Intro - 21
Walther Meißner* 16. Dezember 1882 in Berlin
† 15. November 1974 in Munich
1913 – 1934 building and heading of low temperaturelaboratory at the Physikalisch-Technischen-Reichsanstalt, liquefaction of H2 (20K)
7.3.1925 first liquefaction of He in Germany (4.2 K, 200 ml), 3rd system world-widebesides Leiden and Toronto
1933 discovery of perfect diamagnetism ofsuperconductors together with OchsenfeldMeißner-Ochsenfeld Effect
1934 offer of chair at theTechnische Hochschule München (now TUM)
1946 – 1950 president of the Bayerischen Akademie der Wissenschaften
1946 foundation of the commission for Low Temperature Research Walther-Meißner-Institut
Walther Meißner - der Mann, mit dem die Kälte kamW. Buck, D. Einzel, R. Gross, Physik Journal, Mai 2013
Walther Meißner (1882 – 1974)
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Intro - 25
1935 Fritz and Heinz London
first „quantum mechanical“
theory of superconductivity
(phenomenological)
macroscopic wave function
London equations
Fritz London (1900 – 1954)
Theory of Superconductivity
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Intro - 27
Alexei AbrikosovLev Landau Vitaly Ginzburg
Nobel Prize 2003 Nobel Prize 2003Nobel Prize 1962
"for his pioneering theories for condensedmatter, especially liquid helium"
Nobel Prize in Physics 1962
Lev Davidovich Landau
“for their pioneering contributions to the theory of superconductors and superfluids”
Vitaly Ginzburg, Alexei Abrikosov
Nobel Prize in Physics 2003
(together with Anthony Leggett)
Ginzburg-Landau Theory (1952)
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Intro - 30
J. Bardeen L. N. Cooper R. Schrieffer
Nobel Prize in Physics 1972
"for their jointly developed theory of superconductivity, usually called the BCS-theory"
Microscopic (BCS) Theory (1957)
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Intro - 31
R. Doll M. Näbauer
B.S. DeaverW.M. Fairbank
• Robert Doll Martin Näbauer(Wather-Meißner-Institut)
• Bascom S. DeaverWilliam Martin Fairbanks (Stanford University)
Flux Quantization (1961)
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Intro - 32
(a) (b)
-0.1 0.0 0.1 0.2 0.3 0.4-1
0
1
2
3
4
reso
na
nce
am
plitu
de
(m
m/G
au
ss)
Bcool
(Gauss)
0.0 0.1 0.2 0.3 0.40
1
2
3
4
tra
pp
ed
ma
gn
etic f
lux (
h/2
e)
Bcool
(Gauss)
F0
prediction by Fritz London: h/e first experimental evidence for the existence
of Cooper pairs
Paarweise im Fluss D. Einzel, R. Gross, Physik Journal 10, No. 6, 45-48 (2011)
R. Doll, M. NäbauerPhys. Rev. Lett. 7, 51 (1961)
B.S. Deaver, W.M. FairbankPhys. Rev. Lett. 7, 43 (1961)
Flux Quantization (1961)
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Intro - 34
Brian David Josephson (geb. 04. 01. 1940)
(together with Leo Esaki and Ivar Giaever)
Nobel Prize in Physics 1973
"for his theoretical predictions of the properties of a supercurrent through a tunnel barrier, in particular those phenomena which are generally known as the Josephson effects"
Prediction of the Josephson Effect (1962)
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Intro - 35
Johannes Georg Bednorz * 16. Mai 1950 in Neuenkirchen
im Kreis Steinfurt
Karl Alexander Müller * 20. April 1927 in Basel)
Discovery of the High 𝑇c Superconductivity (1986)
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Intro - 36
J. Georg Bednorz (b. 1950) K. Alexander Müller (b. 1927)
"for their important break-through in the discovery of superconductivity in ceramic materials"
Nobel Prize in Physics 1987
Discovery of the High 𝑇c Superconductivity (1986)
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Intro - 37
Energy TechnologyGenerators, motors,
transformers, fault currentlimiters, magnetic energy
storage, cables
ElectronicsSensors (e.g. SQUIDs), RSFQ Logic, quantum Computing
Medical TechnologyMagnetic resonance imaging, magneto-encephalography,
magneto-cardiography
TrafficShip motors, Superconducting
levitation trains
ProcessingSeparation of ore, water
treatment
Microwave TechnologyFilters, antennas, cavitiesmixers, sources, receivers
Quantum Technology?Quantum computingQuantum simulations
Applications of Superconductivity
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Intro - 39
Superconducting Wires:NbTi, Nb3Sn in Cu-matrix
HTS tapes
Superconducting Wires, Tapes, and Cables
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Intro - 41
• power applications (transport and storage
of energy)energy storage(2 MJ)
current limiter
Applications of superconductivity
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Intro - 42
(Source: Physik Journal 6, 2011)
superconductingfault currentlimiter in thepower stationBoxberg ofVattenfall
Fault Current Limiters
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Intro - 43(Source: Physik Journal 6, 2011)
superconductingrotor forhydroelectricpower station
Generators
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Intro - 44
(So
urc
e: P
hys
ik J
ou
rnal
6, 2
01
1)
production of superconducting solenoids for MRI systemsat Siemens, Erlangen
Superconducting Magnets
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Intro - 45
• transportation systems and traffic
maximum velocity:
581 km/h (02. 12. 2003)
Jap. Yamanashi MAGLEV-System
MLX01
(42.8 km long test track between Sakaigawaand Akiyama, Japan)
Applications of superconductivity
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Intro - 46
Atlas detector
high energy physics• superconducting magnets
MRI systems
fusion
Applications of superconductivity
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Intro - 48
high-field MRI system(for whole-body tomography)
MAGNETOM® AERA 1.5T
integrated MRI-PET systemSiemens Biograph-mMR, 3 T
MRI Systems
Applications of superconductivity
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Intro - 49
Electronics Applications
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Intro - 50
• sensors and detectors
microwave receivers
Quantum interferencedetectors
Applications of superconductivity
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Intro - 52
10-15
10-14
10-13
10-12
10-11
10-10
10-9
10-8
10-7
10-6
10-5
10-4
B (Tesla)
earth magnetic field
urban noise
car @ 50m
screw driver @ 2m
transistor, IC chip @ 2m
single transistor@ 1m
car @ 2km
lung particle
human heartmuscles
foetal hearthuman eyehuman brain (a)
human brain(stimulated)foetal brain
biomagnetic signalsenvironmental noise signals
SuperconductingQuantum Interference
Detector (SQUID)
sensitivity:a few fT/√Hz
1 mmPTB Berlin
Biomagnetism
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Intro - 53
Biomagnetism
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Intro - 54
Source: K. K. Likharev, SUNY Stony Brook
Josephson Computer
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Intro - 55
________________________
Stony Brook____________________________________________
PetaFLOPS Scale Computing:
Speed and Power Scales (Year 2006)
Semiconductors (CMOS)
Performance: > 105 chips @ 10 GFLOPS each
Power: ≈ 150 W per chip total > 15 MW
Footprint: >30 x 30 m2
latency > 3 ms
Superconductors (RSFQ)
Performance: 4·103 processors @ 256 GFLOPS each
Power: ≈ 0.05 W per PE node total 250 W @ 5 K
(100 kW @ 300 K)
Footprint: 1 x 1 m2
latency 20 ns
Source: K. K. Likharev, SUNY
Rapid Single Flux Quantum (RSFQ) Logic
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Intro - 56
Intel dual-core 45 nm
(2007)
first transistor (1947)
Bardeen, Brattain, & Shockley
vacuum tubes
ENIAC (1946)
Enigma (1940)
physics
technology
superconducting Qubit
20 µm
WMI
From mechanical to quantum mechanical IP
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Intro - 57
Flux Qubit
coplanar waveguideresonator1.25 GHz
Q > 105
hybrid ringS23 = - 3 dBS31 = - 50 dB
Superconducting Quantum Circuits
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Intro - 58
David J. WinelandSerge Haroche
The Nobel Prize in Physics 2012 was awarded jointly to Serge Haroche and David J. Wineland "for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems"
The Nobel Prize in Physics 2012
R. G
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study of light – matter interaction on a fundamental quantum level
• consequences of quantum nature of light on light-matter interaction
• quantum mechanical control and manipulation of light and matter
basis for quantum information technology
Cavity QED
Light-matter interaction
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why artificial atoms?
- tunability of (by design & in experiment)
• transition frequency
• selection rules / symmetry
- (ultra) strong coupling to resonator modes T. Niemczyk et al., Nature Physics 6, 772 (2010)
F. Deppe et al. , Nature Physics 4, 686 (2008)T. Niemczyk et al., arXiv:1107.0810v1
Circuit QED
Light-matter interaction
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Intro - 61
fundamental quantum
experiments
solid state quantumtechnology &
quantum sensors
quantuminformation &
communication
Prospects of Circuit QED systems
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Intro - 63
Cluster of ExcellenceNanosystems Initiative Munich (NIM)
spokesman: J. Feldmanncoordinator of RA I -Quantum Nanophysics: R. Gross
Nanosystems
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No! Real „Quantumness“ highly doubted!
Quantum computing- all done?
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Quantum computer
Universal machine to efficientlysolve many types of problems
Example: the simulation ofquantum systems themselves
Always digital Stringent hardware requirements
Current smiconductor-based implementation higly successful Nevertheless inefficient for certain problems, including
Prime number factorization Simulating other quantum systems
Quantum simulator
Encode one hard-to-access quantumsystem in an easier-to-access one
Specialized, not universal Analog or digital variants Dramatically less stringent hardware
requirements
Classical computer
Quantum computing vs. quantum simulation
![Crossover between magnetism and superconductivity in low H ... · arXiv:1406.3450v1 [cond-mat.supr-con] 13 Jun 2014 Crossover between magnetism and superconductivity in low H-doped](https://img.pdfslide.net/doc/110x75/609c61707cb54213fc7c7b5b/crossover-between-magnetism-and-superconductivity-in-low-h-arxiv14063450v1.jpg)
