  We put forward a method for achieving fast and robust for magnetization
reversal in a nanomagnet, by combining the inverse engineering and composite
pulses. The magnetic fields, generated by microwave with time-dependent
frequency, are first designed inversely within short operation time, and
composite pulses are further incorporated to improve the fidelity through
reducing the effect of magnetic anisotropy. The high-fidelity magnetization
reversals are illustrated with numerical examples, and visualized on Bloch
sphere. The influence of damping parameters, relevant to the pulse sequence, is
finally discussed based on Landau-Lifshitz-Gilber equation. These results pave
the way for precise but fast magnetization reversal or switching, with the
applications in high density information storage and processing.
