WHAT IS SUPERCONDUCTIVITY

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WHAT IS SUPERCONDUCTIVITY??
For some materials, the resistivity vanishes at
some low temperature they become superconducting.
Superconductivity is the ability of certain
materials to conduct electrical current with no
resistance. Thus, superconductors can carry large
amounts of current with little or no loss of
energy.
Type I superconductors pure metals, have low
critical field Type II superconductors
primarily of alloys or intermetallic compounds.
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MEISSNER EFFECT
When you place a superconductor in a magnetic
field, the field is expelled below TC.
B
B
T gtTc
T lt Tc
Magnet
Currents i appear, to cancel B. i x B on the
superconductor produces repulsion.
Superconductor
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A superconductor displaying the MEISSNER EFFECT
Superconductors have electronic and magnetic
properties. That is, they have a negative
susceptibility, and 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.
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APPLICATIONS Superconducting Magnetic Levitation
The Yamanashi MLX01MagLev Train
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APPLICATIONS Medical
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APPLICATIONS Power
The cable configuration features a conductor made
from HTS wires wound around a flexible hollow
core. Liquid nitrogen flows through the core,
cooling the HTS wire to the zero resistance
state. The conductor is surrounded by
conventional dielectric insulation. The
efficiency of this design reduces losses.
Superconducting Transmission Cable From American
Superconductor
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