Introduction to Solid State Magnetism

I. Introduction (slides)

• Basic definitions
• Generating magnetic fields
• Link: High magnetic fields labs: (1) Tallahassee/Los Alamos (US), (2) LNCMI Toulouse/Grenoble, (3) FZ Dresden-Rossendorf

II. Short (!) review of magnetism in free atoms (slides)

• Hamiltonian of atoms in an external magnetic field
• Perturbation theory: how to treat the effects of B-field
• Larmor diamagnetism
• Paramagnetism of free atoms, Curie law
• Van Vleck paramagnetism
• Spin-orbit coupling
• Hund's rules
• Hyperfine interaction

III. Atoms in solid: the effect of the crystalline environment (slides)

• Crystal fields: breaking SO(3)
• Symmetry, group theory and the Hamiltonian
• Link: Images representing atomic orbitals
• Link: Character tables and symmetry reduction tool
• Link: R.C. Powell: Symmetry, Group Theory, and the Physical Properties of Crystals: via HEIDI)
• Splitting of 3d-levels in the CF
• High-spin/low-spin configurations
• Quenching of the orbital momentum
• Effect of spin-orbit coupling
• Spin Hamiltonian, g-factor
• Jahn-Teller effect
• Link: H. A. Jahn, E. Teller, Original Work: p. 220 of the Proceedings of the Royal Soc. 161
• Orbital order
• Resonant X-ray scattering
• Link: Resonant Inelastic X-Ray Scattering  at ESRF Grenable
• Link: Orbital order in La7/8Sr1/8MnO3

IV. Cooperative phenomena: on magnetic order(s) (slides)

• Phase transitions (1st/2nd order)
• Landau theory of phase transitions
• Ferromagnetic order
• FM Spin waves
• Bloch's T^3/2-law
• Animation (ext. link): FM spin wave
• Antiferromagnetic order
• Spin-Flop, Spin-Flip
• AFM spin waves
• Animation SLAC (ext. link): AFM spin waves
• Magnetic frustration
• Link: Nobel prize 2021 (chapter V.) (picture on frustration)
• Link: R. Moessner: Review Article on Frustrated Magnetism in Physics Today
• Spin glasses

Magnetoresistance Effect: Spinelectronics (slides)

Magnetism in metals (slides)