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幾何学的フラストレーションの物理:局在スピン系から遍歴電子系まで(集中講義:京都大学大学院理学系研究科): 2013年 夏学期

7月24日
1. General introduction
 1.1. What is "frustration" ?
 1.2. geometrically frustrated lattices
 1.3. What is interesting ?
 1.4. general aspects of frustrated systems
   - suppression of long-range order
   - extensive degeneracy
   - order by disorder
 1.5. extension to itinerant electron systems
2. Ice - from water to spin
 2.1. water ice
 2.2. magnetite Fe3O4
 2.3. spin ice
  - fundamental model
7月25日
 2.3. spin ice (cont'd)
  - fundamental model (cont'd)
  - power-law correlation
  - magnetic monopole
  - role of dipole-dipole interaction
  - effect of magnetic field
3. Triangular lattice systems
 3.1. Ising spin antiferromagnet
 3.2. Heisenberg spin antiferromagnet
 3.3. experiments
 3.4. beyond localized spins
[談話会]
 "Unconventional magnetism and transport in frustrated itinerant systems"
7月26日
4. Kagome lattice systems
 4.1. Ising spin antiferromagnet
 4.2. Heisenberg spin antiferromagnet
 4.3. experiments and beyond localized spins
5. Spinels
 5.1. lattice and electronic structures
 5.2. material matrix of B spinels
 5.3. d3 ACr2O4: pyrochlore Heisenberg antiferromagnet / half magnetization plateau
 5.4. d2 AV2O4: two successive transitions / spin and orbital order
 5.5. d1 MgTi2O4: metal-insulator transition / helical dimerization
 5.6. d2.5 AlV2O4: heptamer formation
 5.3. d1.5 LiV2O4: heavy fermion behavior
6. Pyrochlores
 6.1. lattice structure and materials overview
 6.2. A2Mo2O7
  - metal-insulator transition
  - anomalous Hall effect
  - spin-glass behavior
  - effect of external pressure and carrier doping
 6.3. A2Ir2O7
  - metal-insulator transition
  - spin ice + itinerant electrons
  - effect of external pressure  
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