Fig. 4: Phase difference from effective potentials.
From: Nonlinear dynamics of directly coupled skyrmions in ferrimagnetic spin torque nano-oscillators
a The temporal-averaged total effective potential energy as a function of the relative phase between the two oscillators, with different values of d12. b The phase difference at the local minimum of the potential energy and that from the Thiele’ s equation in the synchronization region. In this calculation, the parameters are the same as those used in Fig. 1.
