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Distance Computation Based on Coupled Spin-Torque Oscillators: Application to Image Processing



Minsuk Koo, Matthew Pufall, Yong Shim, Anthony B. Kos, Gyorgy Csaba, Wolfgang Porod , William Rippard, Kaushik Roy


Recent research on nano-oscillators has shown the possibility of using a coupled-oscillator network as a core-computing primitive for non-Boolean computation. The spin-torque oscillator (STO) is an attractive candidate because it is CMOS compatible, highly integrable, scalable, and frequency and phase tunable. Based on these promising features, we propose an alternative coupled-oscillator-based architecture for hybrid spintronic and CMOS hardware that computes a multidimensional norm. The hybrid system, composed of an array of four injection-locked STOs and a CMOS detector, is experimentally demonstrated. The measured performance is then used as the input to simulations that demonstrate the hybrid system as both a distance metric and a convolution computational primitive for image-processing applications. Energy and scaling analysis shows that the STO-based coupled-oscillatory system has a higher efficiency than the CMOS-based system with an order of magnitude faster computation speed in distance computation for high-dimensional input vectors.
Physical Review


nano-oscillators, coupled-oscillator network, core-computing primitive, non-Boolean computation, spin-torque oscillator, STO, hybrid spintronics, CMOS hardware, four injection-locked STOs, high-dimensional input vectors


Koo, M. , Pufall, M. , Shim, Y. , Kos, A. , Csaba, G. , Porod, W. , Rippard, W. and Roy, K. (2020), Distance Computation Based on Coupled Spin-Torque Oscillators: Application to Image Processing, Physical Review, [online],, (Accessed June 24, 2024)


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Created August 31, 2020, Updated October 12, 2021