奈米磁性薄膜磁光效應量測 及其表面電漿共振增強之研究

Magneto-optical measurement of nano magnetic thin film and enhancement by surface plasmon resonance

許又仁(You-Ren Xu)

指導教授 ： 賴梅鳳

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2012年)

https://doi.org/10.6843/NTHU.2012.00262

摘要

磁異向性用於磁紀錄上很多年，但隨著磁紀錄密度的提升，提高異向性是必要的。本研究結合不同磁區密度之兩種磁性材料，於不同連續膜上製備不同圖形之磁膜陣列，藉由磁光效應量測樣品磁滯曲線探討磁膜間的exchange coupling。結果發現，若在磁性薄膜上製備線及橢圓磁膜陣列，因為線及橢圓本生的形狀異向性，可以微調連續膜的矯頑場，可使本來無磁異向性的磁性薄膜產生不同程度的異向性。此外，由於磁紀錄密度逐年提升，單位磁膜尺度也隨之減小，所以單位磁膜的磁訊號也隨之減小，本實驗延伸製備貴金屬與磁膜的多層膜結構，利用貴金屬表面電漿共振的的特性，探討磁膜磁光效應的增強行為。其結果發現，在貴金屬表面電漿共振的情況下，可使樣品磁光訊號有顯著的提升。

關鍵字

磁光效應 ； 表面電漿 ； 交換耦

並列摘要

Magnetic anisotropy for magnetic record for many years, but with the density enhancement of the magnetic record, the high anisotropy is necessary. This study combines the two material properties of soft magnetic and hard magnetic properties of film. We patterned the magnetic array on the magnetic thin film and study the exchange coupling between the magnetic film by magneto-optical Kerr effect. It was found that magnetic thin film have various degrees of anisotropy because of the shape anisotropy of the magnetic line and elliptic array. In addition, due to the magnetic recording density is increased year by year, the scale of unit magnetic film decreases, the magnetic signal also decreases. In this study we also prepared noble metals and magnetic film multilayer structure, the use of noble metal surface plasmon resonance characteristics to study the enhanced behavior of the magneto-optical signal. Their results showed that the magneto-optical signal enhanced at the surface plasmon resonance condition.

參考文獻

[1] G. Gubbiotti, S. Tacchi and G. Carlotti,” Magnetostatic interaction in arrays of nanometric permalloy wires:A magneto-optic Kerr effect and a Brillouin light scattering study,” PHYSICAL REVIEW B, vol. 72, pp. 224413, 2005.

[2] S. Jain and A. O. Adeyeye, ” Anisotropic magnetostatic interactions in arrays of ellipsoidal shaped Ni80Fe20 magnets,” Vol. 108, pp. 113915, 2010.

[3] D. X. Niu, X. Zou, J. Wu, and Y. B. Xu, “Anisotropic magnetization reversal in 30 nm triangular FeNi dots,” APPLIED PHYSICS LETTERS, Vol. 94, pp. 072501, 2009.

[4] A. Westphalen, A. Schumann, A. Remhof, H. Zabel, T. Last and U. Kunze,” Magnetization reversal of thin Fe triangular rings,” Superlattices and Microstructures, Vol. 41, pp. 98–103, 2007.

[5] J. S. Jiang, J. E. Pearson, Z. Y. Liu, B. Kabius, S. Trasobares, D. J. Miller, S. D. Bader, D. R. Lee, D. Haskel, G. Srajer, and J. P. Liu,” Improving exchange-spring nanocomposite permanent magnets,” Apply Physics Letter, Vol. 85, pp. 5293, 2004.