Fig. 1: Illustration of physical reservoir computing and reservoir based on propagating spin-wave network.
a Schematic illustration of output function prediction by using time-series data. Output signal Y is transformed by past information of input signal U. b Schematic illustration of reservoir computing with multiple physical nodes. The output signal at physical node A contains past input signals in other physical nodes, which are memorized by the reservoir. c Schematic illustration of reservoir computing based on propagating spin-wave. Propagating spin-wave in ferromagnetic thin film (m∥ez) is excited by spin injector (input) through spin-transfer torque at multiple physical nodes with reference magnetic layer (m∥ex) of magnetic tunnel junction. x-component of magnetization is detected by spin detector (output) through magnetoresistance effect using magnetic tunnel junction shown by a cylinder above the thin film at each physical node.
