Influence of rare regions on magnetic quantum phase transitions

Abstract

The effects of quenched disorder on the critical properties of itinerant quantum magnets are considered. Particular attention is paid to locally ordered rare regions that are formed in the presence of quenched disorder even when the bulk system is still in the nonmagnetic phase. It is shown that these local moments or instantons destroy the previously found critical fixed point in the case of antiferromagnets. In the case of itinerant ferromagnets, the critical behavior is unaffected by the rare regions due to an effective long-range interaction between the order parameter fluctuations.

4 pp., REVTeX

References in corpus (1)

• Critical Behavior and Griffiths-McCoy Singularities in the Two-Dimensional Random Quantum Ising Ferromagnet

Cited by in corpus (15)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Quantum phase transitions
• Rare region effects at classical, quantum, and non-equilibrium phase transitions
• Quantum Griffiths effects and smeared phase transitions in metals: theory and experiment
• Disorder-induced rounding of certain quantum phase transitions
• Quantum Griffiths Phase in the weak itinerant ferromagnetic alloy Ni${}_{1-x}$V${}_x$
• Effects of dissipation on a quantum critical point with disorder
• Infinite-randomness quantum critical points induced by dissipation
• Local Defect in Metallic Quantum Critical Systems
• On quantum Griffiths effects in metallic systems
• Dissipation effects in random transverse-field Ising chains
• On the critical behavior of disordered quantum magnets: The relevance of rare regions
• Order parameter symmetry and mode coupling effects at dirty superconducting quantum phase transitions
• Quenched disorder at antiferromagnetic quantum critical points in $2d$ metals
• The effect of rare regions on a disordered itinerant quantum antiferromagnet with cubic anisotropy