METAMAGNETISM IN FRUSTRATED SPIN CHAINS

MARCELO ARLEGO; FABIAN HEIDRICH-MEISNER; ANDREAS HONECKER; GERARDO ROSSINI; TEIMURAZ VEKUA

Natal

Workshop; Geometrically Frustrated Magnets: from spin ice to kagome planes; 2011

International Institute of Physics

We show that frustrated, SU(2)-symmetric spin-S chains with ferromagnetic nearest-neighbor interactions exhibit metamagnetic behavior under the influence of an external magnetic field for small S, in the form of a first-order transition to the fully polarized state. The magnetization jump increases gradually starting from an S-dependent critical value of exchange couplings and takes a maximum in the vicinity of a Lifshitz point. The metamagnetism results from resonances in the dilute magnon gas caused by an interplay between quantum fluctuations and frustration.