INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Metamagnetism in frustrated ferromagnetic spin S chains
HEIDRICH-MEISNER FABIAN; ARLEGO MARCELO; HONECKER ANDREAS; ROSSINI GERARDO; VEKUA TEMOURAZ
Workshop; Workshop on Synergies between Field Theory and Exact Computational Methods in Strongly Correlated Quantum Matter; 2011
ICAM-I2CAM Institute for Complex Adaptive Matter and Boston University
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 ≥ 1, 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. Our predictions are verified numerically byprecise density matrix renormailzation group (DMRG) and exact diagonalization (ED) calculations on S = 1, 3/2, 2 systems.