Interconnects for All-Spin Logic Using Automotion of Domain Walls

In this paper, an interconnect scheme based on automotion of domain walls (DWs) for all-spin logic (ASL) has been proposed. The proposed interconnect is analyzed using a comprehensive numerical model including an equivalent circuit for ASL operations, the 1-D Landau-Lifshitz-Gilbert equation for DW creation, reflection, and disappearance at the boundaries. Analytical expressions for DW transport along the wire are also presented. From the model, it is found that the reflection of the DW can be eliminated using a material with a high Gilbert damping coefficient at the end, the energy dissipation can be independent of the interconnect length, and DW displacement and energy dissipation can be further improved using a material with a low damping factor and saturation magnetization. Furthermore, the interconnect reliability is also studied by applying the thermal random noise analysis on the dynamics of DWs, and it is found that thermal fluctuations can have a significant impact on the interconnect performance; thus, the interconnect with a low Gilbert damping factor is desired to suppress the thermal noise effects.

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