Abstract:

Spin Hall nano oscillator (SHNO), a new type spintronic nano-device, can generate microwave signal and excite coherent spin waves due to spin current-driven magnetization precession and have strong potential for applications from data storage，rf communication, microwave generation to neuromorphic computing. In this review, we focus on the complex nonlinear dynamic characteristics of spin-wave modes generated by SHNOs in the various ferromagnetic/nonmagnetic (FM/NM) bilayer systems with an extended free layer. Based on the abundantly previous experimental results obtained by combining microwave spectroscopy and micro-focused Brillouin light scattering techniques, as well as micromagnetic simulation, we detailedly describe and summarize the experimental parameters dependent magnetic dynamics of SHNOs with different device configurations and magnetic materials, such as in-plane nanogap-type, nanoconstriction-type, nanowire-type, vertical nanocontact-type SHNOs with in-plane or out-of-plane magnetization. Finally, we also discuss mutual synchronization of SHNO arrays and the potential applications in magnon-based logic devices with ultralow energy consumption and spin-based artificial neural network for neuromorphic computing in the field of artificial intelligence.

Key words: spin Hall nano-oscillator, spin-orbit torque, spin-waves, mutual synchronization