TY  - JOUR
AU  - Perroni, C. A.
AU  - Liebsch, A.
TI  - Magnetization dynamics in dysprosium orthoferrites via the inverse Faraday effect
JO  - Physical review / B
VL  - 74
IS  - 13
SN  - 1098-0121
CY  - College Park, Md.
PB  - APS
M1  - PreJuSER-57121
SP  - 134430
PY  - 2006
N1  - Record converted from VDB: 12.11.2012
AB  - The ultrafast nonthermal control of magnetization has recently become feasible in canted antiferromagnets through photomagnetic instantaneous pulses [A. V. Kimel , Nature 435, 655 (2005)]. In this experiment, circularly polarized femtosecond laser pulses set up a strong magnetic field along the wave vector of the radiation through the inverse Faraday effect, thereby exciting nonthermally the spin dynamics of dysprosium orthoferrites. A theoretical study is performed by using a model for orthoferrites based on a general form of free energy whose parameters are extracted from experimental measurements. The magnetization dynamics is described by solving coupled sublattice Landau-Lifshitz-Gilbert equations whose damping term is associated with the scattering rate due to magnon-magnon interaction. Due to the inverse Faraday effect and the nonthermal excitation, the effect of the laser is simulated by magnetic-field Gaussian pulses with temporal width of the order of 100 fs. When the field is along the z axis, a single resonance mode of the magnetization is excited. The amplitude of the magnetization and out-of-phase behavior of the oscillations for fields in the z and -z directions are in good agreement with the cited experiment. The analysis of the effect of the temperature shows that the magnon-magnon scattering mechanism affects the decay of the oscillations on the picosecond scale. Finally, when the field pulse is along the x axis, another mode is excited, as observed in experiments. In this case, a comparison between theoretical and experimental results shows some discrepancies, the origin of which is related to the role played by anisotropies in orthoferrites.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000241723200081
DO  - DOI:10.1103/PhysRevB.74.134430
UR  - https://juser.fz-juelich.de/record/57121
ER  -