Superconductors exhibit nearly zero electrical resistance and perfect diamagnetism below a certain transition temperature, enabling them to conduct electricity without energy loss. They have significant applications in medical imaging, computing, and magnetic energy storage due to their ability to carry large currents and generate strong magnetic fields. The behavior of superconductors is explained by theories such as London theory and the Bardeen-Cooper-Schrieffer theory, which describe the formation of Cooper pairs that allow for resistance-free electron flow.

2. Super conductivity
General properties
Observations regarding
Applications

3.  Super conductor are the material having
almost zero resistivity and behave as
diamagnetic below the super conducting
transition temperature.
 Super conductors are PERFECT conductors.

4.  Virtually zero electrical resistance.
 Perfect diamagnetic property.
 Critical field depends upon temperature of superconducting
material.
 Heavy current effect destroys superconductivity properties.
 At very high pressure Tc is directly proportional to pressure.
 Tc is inversely proportional to square root of At.wt of the
isotope of single superconductor.

5.  LONDON THEORY -1935
 GINZBURG-LANDAU THEORY – 1950
 BARDEEN, COOPER, SCHRIEFFER THEORY - 1957

6. Principle:
The electron experience a special kind of attractive
interaction, over coming the coulombs force of repulsion between
them, as a result cooper pairs are formed.
At low temperature , these pairs move through lattice
without resistance and hence behave as superconductor.

7. Super conductor lattice

8. Due to attract of electron by positive
charge, ions in conductor is disturbed

9. Ions attracted by positive charges

10. Due to deformation
positive charge increased

11. Electrons get attracted due to
increased positive charges

12. Cooper pairs formed

13.  Can carry large quantities of energy without heat loss.
 Able to generate strong magnetic fields.
 Superconductors beneficial applications in medical
imaging techniques.
 New superconductive films may result in
miniaturization .
 Superconductors increased speed in computer chips.

14.  Superconducting materials conduct current
at only given temperature known as
transition temperature.
 Superconductorsstill do not show up in most
everyday electronics.

15. Principle:
Persistent current in D.C voltage.
Construction:
A thin layer of insulators is placed between the
superconductors.
Both superconductors are connected to a battery .
Working :
LET US SEE THE WORKING OF JOSEPH
DEVICE IN THE SUCCEEDING SLIDES.

16. Josephson devices

17. Voltage V applied across
super conductor 1

18. Current increases due to
tunneling effect

19.  Super conducting generator
 Super conducting transmission line cables
 Superconducting magnetic energy storage system (smes)

20.  Converts mechanical to electrical energy.
 Own magnetic field is produced.
 Current and flux density determines the output.
 Field windings produces higher magnetic field.
 Superconductors have extremely high current
carrying capacity.

22.  Provides ZERO resistance.
 Due to LOW VOLTAGE, high current transmission
occurs.
 SMALL physical size.
 Reduced CLEARANCE for terminal faculties.
 Quick RECOVERY after fault.
 Overload capability.

23.  Current carrying wire generates a magnetic
field.
 Superconducting solenoids made by wrapping
a superconducting wire in the coil from are
functionally superior to conventional
solenoids.
 Zero DC electrical resistance.
 No resistive losses.

26. Thank you !