Two-dimensional mutually synchronized spin Hall nano-oscillator arrays for neuromorphic computing
Top Cited Papers
- 23 December 2019
- journal article
- research article
- Published by Springer Science and Business Media LLC in Nature Nanotechnology
- Vol. 15 (1), 47-52
- https://doi.org/10.1038/s41565-019-0593-9
Abstract
In spin Hall nano-oscillators (SHNOs), pure spin currents drive local regions of magnetic films and nanostructures into auto-oscillating precession. If such regions are placed in close proximity to each other they can interact and may mutually synchronize. Here, we demonstrate robust mutual synchronization of two-dimensional SHNO arrays ranging from 2 × 2 to 8 × 8 nano-constrictions, observed both electrically and using micro-Brillouin light scattering microscopy. On short time scales, where the auto-oscillation linewidth \(\Delta f\) is governed by white noise, the signal quality factor, \(Q=f/\Delta f\), increases linearly with the number of mutually synchronized nano-constrictions (N), reaching 170,000 in the largest arrays. We also show that SHNO arrays exposed to two independently tuned microwave frequencies exhibit the same synchronization maps as can be used for neuromorphic vowel recognition. Our demonstrations may hence enable the use of SHNO arrays in two-dimensional oscillator networks for high-quality microwave signal generation and ultra-fast neuromorphic computing.
Keywords
This publication has 47 references indexed in Scilit:
- Nanoconstriction-based spin-Hall nano-oscillatorApplied Physics Letters, 2014
- Synchronization of spin Hall nano-oscillators to external microwave signalsNature Communications, 2014
- Spin-torque building blocksNature Materials, 2013
- Magnetic nano-oscillator driven by pure spin currentNature Materials, 2012
- Nonwhite frequency noise in spin torque oscillators and its effect on spectral linewidthPhysical Review B, 2010
- Impact of the electrical connection of spin transfer nano-oscillators on their synchronization: an analytical studyApplied Physics Letters, 2008
- Generation Linewidth of an Auto-Oscillator with a Nonlinear Frequency Shift: Spin-Torque Nano-OscillatorPhysical Review Letters, 2008
- Synchronized Oscillation in Coupled Nanomechanical OscillatorsScience, 2007
- Current-driven microwave dynamics in magnetic point contacts as a function of applied field anglePhysical Review B, 2004
- Phase-locked oscillator optimization for arrays of Josephson junctionsJournal of Applied Physics, 1994