Transcript Superfluidity in correlated fermions: From high Tc

Superconductivity Narratives
The Players:
The Applications:
And the Future:
Subtitle: The Human side of
“Table Top” Physics
Graduate Students, Nobel and
Ig Nobel prizes…
Superfluidity and
Superconductivity Associated
with at Least Nine Nobel Prizes
And Still counting …
Nobel Laureates
L. Landau and Phil Anderson
And Possible Laureates….
Kammerlingh Onnes
discovered superconductivity
1911
Failed Theories of
Superconductivity
Bardeen Cooper Schrieffer
discovered theory of
superconductivity 1957
Electrons pair and do
the Cooper pair “dance”
Brian Josephson Discovered
Quantum Interference in
Superconductors (Josephson
Effect) 1964
Currently Runs Mind-Matter Unification Project
Osheroff, with Richardson
and Lee
discovered superfluid
helium-3 in 1973
Bednorz and Muller
Discovered High
Temperature
Superconductors 1986
The Discovery of Higher Tc
Superconductors and
The Paul Chu
Green Superconductor Saga
The “Woodstock” American
Physical Society Meeting 1987
The Human side of Physicists --all
night session on High Tc
superconductivity
Transition temperature vs time
Key Discovery: Superconducting transition
temperatures above liquid nitrogen boiling temp–
cheap coolant available
Highest Transition Temperature -189 F !
HighTemperature
Superconductors
(up to ~150K)
Boiling Water
212
100
373
Conventional
Superconductors
(up to ~-405 F)
Ice
Liquid nitrogen
Absolute Zero
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0
273
-290
-196
77
-273
0
-460
WHAT IS SUPERCONDUCTIVITY??
For superconducting materials, the resistivity vanishes
at some low temperature.
Thus, superconductors can carry
large amounts of current with no
loss of energy.
What Else Can
Superconductors Do ?
Expel magnetic fields:
Meissner effect
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Allow a current in a closed circuit to persist
indefinitely.
The Meissner Effect
Levitation of Sumo wrestler– Ig Nobel
Prize
Superconductors acquire a polarization OPPOSITE to an applied magnetic field. This
is the reason that superconducting materials and magnets repel one another.
If the temperature increases the sample will lose its superconductivity and the
magnet cannot float on the superconductor.
What superfluids can do
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Flow without viscosity
Dribble through molecule thin cracks
Climb up and over the sides of a dish
Remain motionless when the container is
spun.
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Applications using Superconductors
MRI Body scanners
Accelerator magnets
Magnetometers for
medicine,
seismography …
Transport
Power transmission
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Applications using Superconductors
Transport
In Jan 08, the Central Japan Railway Company (JR Central)
announced that it plans to construct a second-generation maglev
train that will run from Tokyo to central Japan.
Cost ~ 44.7 billion dollars
Completion in 2025
Speed ~ 500 kilometers per hour
Length ~ 290 kilometers
Maglev train: Superconductivity at 500
km/hr
Existing Japanese MagLev train
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Yamanashi Test Site, Japan
33 km long, >500 Km/hr
Segment of Tokyo-Osaka new
line
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Applications using Superconductors
Superconducting power transmission
- currently we waste ~ 20 % of our
energy just transporting it around
- potentially the next industrial
revolution
Long Distance DC
Superconducting Electricity
Pipeline
MRI Uses Superconducting
Magnets
Closed (1-3 Tesla) and open (0.3T) MRI magnets both use Nb-Ti with a
transition temperature (Tc) of only 9K, ~-450F.
All are Cooled only by liquid helium until late 2006 .
MRI - $1B annual market
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Superconducting Magnetometers
based on Josephson Effect
Particle Accelerators Use
Superconducting magnets
Superconducting
Tevatron
energy-saver
accelerator rings
west of Chicago
(Batavia, IL)
Nb-Ti at 4.5 T,
4.2 K
Mont Blanc
Large Hadron Collider-CERN
Lake Geneva
Switzerland
27 km Tunnel
France
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Some facts about the LHC
Protons are accelerated to 99.999999991% of the speed
of light
The LHC lets us glimpse the conditions 1/100th of a
billionth of a second after the Big Bang: a travel back in
time by 13.7 billion years
High energy collisions create particles that haven’t
existed in nature since the Big Bang
Find out what makes the Universe tick at
the most fundamental level
And find the Higgs boson!
Concept of Higgs Boson– comes
from superconductivity theory
LHC –Depends on
Superconductivity
3286 HTS Leads
Applications of HighTemperature Superconductivity
Today:
• Over 5,500 cell-phone towers contain hightemp SCs
• 3 Prototype substations for power transmission
in US
• Other markets being developed
1911-2011
100 Years of Remarkable
Progress
Superconducting devices are pervasive in
science and medical technologies
• Frictionless current flow allows multiple
applications.
• Deep principles behind superconductivity
(esp. High Tc superconductivity) to be
discovered– more Nobel Prizes(?)
The Applied Superconductivity Center
The National High Magnetic Field Laboratory - FSU
What do we dream of?
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Materials that remain superconducting in any field.
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Materials that carry enormous current densities so
that we can make very powerful magnets.
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Materials that are cheap to make, flexible in use,
versatile in design and manufacture, strong,
fracture resistant.
Summary
Superconductivity offers excellent
science, excellent technology, excellent
training and the possibility of saving the
planet !!
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What Else Do We Dream of ?
Even Better Super Conductors!