Scalable synchronization of spin-Hall oscillators in out-of-plane field

A strategy for a scalablesynchronization of an array of spin-Halloscillators (SHOs) is illustrated. In detail, we present themicromagnetic simulations of two and five SHOs realized by means of couples of triangular golden contacts on the top of a Pt/CoFeB/Ta trilayer. The results highlight that thesynchronization occurs for the whole current region that gives rise to the excitation of self-oscillations. This is linked to the role of the magnetodipolar coupling, which is the phenomenon driving thesynchronization when the distance betweenoscillators is not too large.Synchronization also turns out to be robust against geometrical differences of the contacts, simulated by considering variable distances between the tips ranging from 100  nm to 200 nm. Besides, it entails an enlargement of the radiation pattern that can be useful for the generation of spin-waves in magnonics applications. Simulations performed to study the effect of the interfacial Dzyaloshinskii-Moriya interaction show nonreciprocity inspatial propagation of the synchronized spin-wave. The simplicity of the geometry and the robustness of the achievedsynchronization make this design of array of SHOs scalable for a larger number of synchronizedoscillators.

Source: Applied Physics Letters - November 14, 2016 Category: Physics Authors: V. Puliafito, A. Giordano, A. Laudani, F. Garesc ì, M. Carpentieri, B. Azzerboni and G. Finocchio Source Type: research