本實驗採用熱蒸鍍法製備數組Cu 奈米微粒，經過氧化後形成 Cu/Cu2O 奈米微粒，最後採用三組樣品粒徑分別為3.4 nm、2.3 nm 與3.9 nm。並使用物理特性量測系統(Physical property measurement system)量測其磁性，利用朗之萬函數(Langevin function)加上一線性項擬合實驗，此線性項為順磁與反磁一起貢獻的結果，進而分析其磁性。 在塊材的銅與氧化亞銅皆為反磁性，但此實驗發現在低磁場部分 由鐵磁性表現，高磁場則為銅與氧化亞銅共同表現的現象，當溫度升高時反磁現象越明顯，不過當Cu2O 變多時反而是使反磁性降低。由此也可推測出核內的銅在奈米尺度下能為反磁性，但氧化亞銅則與塊材實的磁性有所不同。在磁矩與溫度的關係上，則發現磁矩排列隨溫度上升而變大的特性，μP ~ kBT。而造成這些與塊材磁性相異的原因，推測乃因表面電子自旋極化與Cu/Cu2O 部分氧缺陷所造成。 Copper nanoparticles were fabricated by the thermal evaporation method. A series of copper nanoparticles were oxided to form core-shell structure. The diameters of 3.4 nm, 2.3 nm and 3.9 nm Cu/Cu2O nanoparticles were determined by atomic force microscope images. We observe the spin polarization in Cu/Cu2O fine particles. The applied magnetic field dependency of magnetization (M-H curve) can be described by using Langevin function. And we also find two magnetic components in Cu/Cu2O nanoparticles at low temperatures. We can find that the fitting parameters μp increase with increasing temperature. According to ferromagnetic component in M-H curves and remanence, the ferromagnetic spin polarization of Cu/Cu2O nanoparticles is observed.
