Phase locking dynamics of dipolarly coupled vortex-based spin transfer oscillators

Phase locking dynamics of dipolarly coupled vortices excited by spin-polarized current in two identical nanopillars is studied as a function of the interpillar distance L. Numerical study and an analytical model have proved the remarkable efficiency of magnetostatic interaction in achieving phase locking. Investigating the dynamics in the transient regime toward phase locking, we extract the evolution of the locking time τ, the coupling strength μ, and the interaction energy W. Finally, we compare this coupling energy with the one obtained by a simple model.