Download Electron discovered 1897, Thomson Atom model 1913, Bohr

Quantum Mechanics
1925, Heisenberg,
Schrödinger
Electron discovered
1897, Thomson
Atom model
1913, Bohr, Rutherford
???
High-Tc discovered
1986, Bednorz, Müller
Bloch’s 2nd theorem:
All theories of SC are
wrong!
Superconductivity discovered
1911, Kammerlingh Onnes
Meissner effect
1933-35, London
BCS theory
1957
Maxwell’s equations
In materials
Meissner - London
Diamagnetism – Quantum Mechanics
Momentum, velocity, magnetic field:
Diamagnetic current,
reduces the magnetic
moment
Quantized angular momentum:
quantized
What determines the current ?
Ginzburg- Landau (1950): Equilibrium thermodynamics,
Free energy
Fermions - Bosons
•
•
•
•
Fermions
Electrons
Pauli principle
All have to behave
differently
• Bosons
• Fotons, He4, even
number of fermions
• Inverse Pauli principle
• Prefer to behave alike
• Bose-kondensation
What is
?
Bardeen – Cooper – Schrieffer (1957)
Degenerate
electron gas
Fermi-sphere
Quasiparticles
BCS-theory, Cooper pairs
BCS ground state: Bose condensate of Cooper pairs
Cooper pairs - Impurities
s-, d-, p-waves
Cooper pair is a pair of fermions:
Exchanging particles should give minus !
Spin states:
Orbital states:
Singlet (s=0, odd)
s (l=0, even), d (l=2, even)
Triplet (s=1, even)
p (l=1, odd)
s
d (strong repulsion)
p (ferromagnetic)
The Higgs particle