Microcoils for Magnetisation Reset in Stroboscopic Optical Pump-Probe Experiments

Magneto-optical pump-probe techniques allow for the measurment of magnetic behaviours on femtosecond timescales. It is common in pump-probe setups for the sample magnetisation to be reset between pump-probe pairs using a continuously applied external magnetic field. Continuously applied reset fields can obscure aspects of the dynamics, particularly those relevant to the study of multiple pulse all-optical magnetisation switching. Here we introduce a pulsed microcoil device capable of magnetisation reset with tunable repetition rate. The pulsed-field induced switching is examined for magnetic multilayer and insulating magnetic garnet samples with out-of-plane anisotropy, and indicates the generation of fields up to 150 mT at frequencies up to 200 kHz.