自旋霍爾效應(SHE)與反自旋霍爾效應(ISHE)同時作用造成磁阻的改變，所以稱之為自旋霍爾磁阻(SMR)。本研究中，希望透過鉑(Pt)與鎳鋅鐵氧(NZFO)的雙層結構得到室溫下，電流轉換為自旋流之比例自旋霍爾角spin hall angle θ_SH；以及鉑之自旋擴散長度 spin diffusion length λ_Pt。再利用外加一層磁性金屬，提升整體MR變化率。

The Spin Hall Magnetoresistance (SMR) effect is come from the spin hall effect (SHE) and inverse spin hall effect (ISHE), observed by Nakayama et al. In this work, we studied angular dependent MR in Pt/NZFO, CoFe/Pt and CoFe/Pt/NZFO multilayer systems. Based on field dependent and angular dependent magnetoresistance results, SMR exists in all multilayer system. Using the SMR theory to analyze our data, the spin hall angle and spin diffusion length of platinum can be obtained. Additionally, the SMR ratio of trilayer structure is much larger than both Pt/NZFO and CoFe/Pt bilayer systems. This enhancement of trilayer structure is significant success for spintronics devices.

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