Magnon Bose condensation in symmetry breaking magnetic field

Abstract

Magnon Bose condensation (BC)in the symmetry breaking magnetic field is a result of unusual form of the Zeeman energy, which has terms linear in the spin-wave operators and terms mixing excitations differ in the Wave-vector of the magnetic structure. The following examples are considered: simple easy-plane tetragonal antiferromagnets (AF), frustrated AF family$R_{2}Cu{O}_4$ where $R=Pr,Nd$ etc. and cubic magnets with the Dzyaloshinskii-Moriya interaction ($MnSi$ etc.). In all cases the BC becomes important when the magnetic field becomes comparable with the spin-wave gap. The theory is illustrated by existing experimental results.

arXiv commentSubmitted to J. of Phys. Condens. Matter (Proceedings of International Conference "Highly Frustrated Magnets", Osaka (Japan), August 2006). 8 pages, 5 figures

References in corpus (4)

• Anisotropic Spin Hamiltonians due to Spin-Orbit and Coulomb Exchange Interactions
• Cubic magnets with Dzyaloshinskii-Moriya interaction at low T
• Quantum Phase Transition in Pr2CuO4 to Collinear Spin State in Inclined Magnetic Field: A Neutron Diffraction Observation
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