Anulekha De

For nearly 90 years, precession and relaxation processes have been thought to dominate the magnetization dynamics. Only recently has it been considered that, on short time scales, an inertia-driven magnetization dynamics should become relevant, leading to additional nutation of the magnetization vector.

Understanding spin dynamics on femto- and picosecond timescales offers new opportunities for faster and more efficient spintronic devices. Here, we experimentally investigate the coherent spin dynamics after ultrashort laser excitation by performing time-resolved magneto-optical Kerr effect experiments with thin Ni80Fe20 films. We provide a detailed study of the magnetic field and pump fluence dependence of the coherent precessional dynamics after optical excitation with femtosecond laser pulses.