利用X光吸收光譜和磁圓偏振二向性研究三層膜Pd/Co/Pd/Al2O3的電子結構及磁性特質

Magnetism and Electronic Structure of Pd/Co/Pd/Al2O3 Trilayer Studied by X-ray Absorption Spectroscopy and Magnetic Circular Dichroism

高肇鴻(Chao-Hung Kao)

指導教授 ： 彭維鋒

淡江大學/理學院/物理學系碩士班/碩士(2014年)

https://doi.org/10.6846/TKU.2014.01046

摘要

此篇之研究報告發現Pd/Co/Pd三層膜結構透過退火處理產生垂直磁異向性 (Perpendicular Magnetic Anisotropy, PMA)，藉由X 光吸收近邊緣結構(X-ray Absorption Near Edge Structure)以及延伸X 光吸收精細結構(Extend X-ray Absorption Fine Structure)結果對比合金樣品，可以發現退火效應誘發合金結構。進一步利用X光磁圓偏振二向性(X-ray Magnetic Circular Dichroism)可以發現退火效應導致樣品軌道/自旋磁矩比增強因而改變樣品的磁性異向性，因此我們推論Pd/Co/Pd三層膜透過了退火改變了結構同時也誘發了樣品的垂直磁異向性。

關鍵字

鈀 ； 鈷 ； 退火 ； 合金 ； 吸收譜 ； 垂直磁性

並列摘要

In Pd/Co/Pd trilayers, we report that the perpendicular magnetic anisotropy (PMA) can be induced by a modification of Pd-Co interface through the post-annealing. By means of magneto-optical Kerr effect, X-ray absorption near-edge structure, extended X-ray absorption fine structure, and X-ray magnetic circular dichroism, we demonstrate that the post-annealing could lead to formation of alloy-like Co structure above the preceding Pd-Co interface. Such interface structure could enhance the PMA owing to the characteristics of perpendicular crystalline anisotropy.

並列關鍵字

Pd/Co/Pd ； XMCD ； XANES ； EXAFS ； Alloy ； PMA

參考文獻

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