Dynamical exchange and phase induced switching of a localized molecular spin

The dynamics of a localized molecular spin under the influence of external voltage pulses is addressed using a generalized spin equation of motion. The approach incorporates anisotropic fields, non-equilibrium conditions, and non-adiabatic dynamics. By application of a voltage pulse of temporal length $\tau$, a recurring $4\pi$-periodic switching of the localized spin is observed. The switching phenomena can be explained by dynamical exchange interactions, internal transient fields, and self-interactions acting on the localized spin moment.