本研究中，探討鈷鐵氧體(CoFe2O4；CFO)與釕酸鍶(SrRuO3；SRO)奈米複合材料間的應變耦合關係。其中，磁致伸縮(magnetostriction)型感測器中，具有亞鐵磁性與磁晶異向性的鈷鐵氧體為一個廣泛討論的材料，而有良好的導電性和導熱係數的釕酸鍶(SrRuO3；SRO)，也具有光致伸縮(photostriction)的特性。當鈷鐵氧體和釕酸鍶成長在一起時，易形成奈米柱狀的結構。本研究擬利用拉曼光譜儀(Raman Spectroscopy)，量測複合結構材料中釕酸鍶-鈷鐵氧體於外加磁場的過程中，由於鈷鐵氧體的磁致伸縮性質，而造成鈷鐵氧體奈米晶柱(pillars)的晶體形變，進而影響釕酸鍶基材(matrix)的結構變化。並透過變溫拉曼光譜的量測分別觀察在釕酸鍶和鈷鐵氧體的居里溫度附近，譜線相對應的變化。最後利用磁力顯微鏡(MFM)，進一步探討釕酸鍶基材的光致伸縮性質，影響鈷鐵氧體奈米晶柱的磁矩排列。

In this study, strain couplings in the SrRuO3 and CoFe2O4 nano-composites were investigated. CoFe2O4 (CFO), which has ferrimagnetism and magnetic anisotropy property, is widely discussed for the application of the magnetostriction-based sensors, while SrRuO3(SRO), which has good electrical and thermal conductivities, is also known for its photostrictive property. When CoFe2O4 and SrRuO3 are synthesized simultaneously, it is easy to form nanopillars structures. In this study, I used Raman spectroscopy to investigate the distortions of SrRuO3-CoFe2O4 nano-composites under external magnetic fields. The crystal structures of SrRuO3 matrix are affected by the deformation of the CoFe2O4 pillars through the magnetostrictive couplings. The variations of Raman phonons of the nano-composites near the Curie temperatures (Tc) of SrRuO3 and CoFe2O4 were also studied by temperature-dependent Raman measurements. Finally, under the light illumination, the reorientation of magnetic moments in CoFe2O4 nanopillars arising from the photostrictive properties of SrRuO3 were demonstrated by magnetic force microscopy (MFM).

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