Unconventional magnets in external magnetic fields

Abstract

This short review surveys phenomena observed when a magnetic field is applied to a system of localised spins on a lattice. Its focus is on frustrated magnets in dimension $d\ge 2$. The interplay of field and entropy is illustrated in the context of their unusual magnetocaloric properties, where field-tuned degeneracies assert themselves. Magnetisation plateaux can reveal the physics of fluctuations, with unusual excitations (such as local modes, extended string defects or monopoles) involved in plateau termination. Field-tuning lattice geometry is the final topic, where mechanisms for dimensional reduction and conversion between different lattice types are discussed.

Plenary Talk at HFM 2008 Conference

References in corpus (28)

• Anyons in an exactly solved model and beyond
• Bose-Einstein Condensation in Magnetic Insulators
• Dipolar Interactions and Origin of Spin Ice in Ising Pyrochlore Magnets
• Aharonov-Bohm cages in two-dimensional structures
• Band touching from real space topology in frustrated hopping models
• Macroscopic magnetization jumps due to independent magnons in frustrated quantum spin lattices
• Nematic order in square lattice frustrated ferromagnets
• Long Range Order at Low Temperature in Dipolar Spin Ice
• Enhanced magnetocaloric effect in frustrated magnets
• Order by distortion and string modes in pyrochlore antiferromagnet
• Spin Driven Jahn-Teller Distortion in a Pyrochlore system
• Direct Measurement of the Spin Hamiltonian and Observation of Condensation of Magnons in the 2D Frustrated Quantum Magnet Cs2CuCl4
• Half-magnetization plateau stabilized by structural distortion in the antiferromagnetic Heisenberg model on a pyrochlore lattice
• Why spin ice obeys the ice rules
• Exact low-temperature behavior of kagome antiferromagnet at high fields
• Spinons and triplons in spatially anisotropic frustrated antiferromagnets
• Theory of the [111] magnetization plateau in spin ice
• Field induced transitions in a kagome antiferromagnet
• Pinch Points and Kasteleyn Transitions: How Spin Ice Changes its Entropy
• Magnetization process of spin ice in a [111] magnetic field
• Finite Temperature Transitions in Large Magnetic Field in Dipolar Spin Ice
• Magnets with strong geometric frustration
• Magnetization plateaus of SrCu_2(BO_3)_2 from a Chern-Simons theory
• Quantum kagome antiferromagnet in a magnetic field: Low-lying non-magnetic excitations versus valence-bond crystal order
• Bond order from disorder in the planar pyrochlore magnet
• Order by disorder and gauge-like degeneracy in quantum pyrochlore antiferromagnet
• Magnetization plateaus and sublattice ordering in easy axis Kagome lattice antiferromagnets
• Semiclassical degeneracies and ordering for highly frustrated magnets in a field

Cited by in corpus (5)

• Magnetic phase diagrams of classical triangular and kagome antiferromagnets
• New physics in frustrated magnets: Spin ices, monopoles, etc
• Novel phases in a square-lattice frustrated ferromagnet : 1/3-magnetisation plateau, helicoidal spin-liquid and vortex crystal
• Itinerant electrons in the Coulomb phase
• Magnetization process and ordering of the $S=1/2$ pyrochlore magnet in a field