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arXiv · 2103.02724

Skyrmion Logic Clocked via Voltage Controlled Magnetic Anisotropy

Benjamin W. Walker·Can Cui·Felipe Garcia-Sanchez·Jean Anne C. Incorvia·Xuan Hu·Joseph S. Friedman
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Abstract

Magnetic skyrmions are exciting candidates for energy-efficient computing due to their non-volatility, detectability,and mobility. A recent proposal within the paradigm of reversible computing enables large-scale circuits composed ofdirectly-cascaded skyrmion logic gates, but it is limited by the manufacturing difficulty and energy costs associated withthe use of notches for skyrmion synchronization. To overcome these challenges, we therefore propose a skyrmion logicsynchronized via modulation of voltage-controlled magnetic anisotropy (VCMA). In addition to demonstrating theprinciple of VCMA synchronization through micromagnetic simulations, we also quantify the impacts of current den-sity, skyrmion velocity, and anisotropy barrier height on skyrmion motion. Further micromagnetic results demonstratethe feasibility of cascaded logic circuits in which VCMA synchronizers enable clocking and pipelining, illustrating afeasible pathway toward energy-efficient large-scale computing systems based on magnetic skyrmions.

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Benjamin W. Walker, Can Cui, Felipe Garcia-Sanchez, Jean Anne C. Incorvia, Xuan Hu, Joseph S. Friedman. 2021-03-05. Skyrmion Logic Clocked via Voltage Controlled Magnetic Anisotropy. https://doi.org/10.1063/5.0049024

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