Suppression of Dynamically Induced Stochastic Magnetic Behaviour through Materials Engineering

Stochastic behaviour fundamentally limits the performance and reliability of nanomagnetic devices. Typically, stochastic behaviour is assumed to be the result of simple thermal activation, but it may also be "dynamically induced" i.e. a direct result of the spatial and temporal complexity of magnetisation dynamics. In this paper, we show how materials engineering can be used to comprehensively suppress dynamically induced stochasticity. Using the dynamics of magnetic domain walls in Ni80Fe20 nanowires as a case study we show how manipulation of the Gilbert damping constant via doping with the rare earth element Terbium dramatically simplifies domain wall dynamics. This allows us to obtain quasi-deterministic behaviours from systems that nominally exhibit exceptionally high levels of stochasticity