Large magnetic circular dichroism of Co clusters in Co-doped Amorphous Carbon

• Main Authors: W. Y. Su, 蘇汶元
• Other Authors: J. H. Huang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/88398914030682715095

碩士 === 國立高雄師範大學 === 物理學系 === 99 === Amorphous carbon (a-C) amorphous semiconductor with a mi- xture of graphite–like sp2 and diamond-like sp3 bond cha- racters, which features the extra degrees of freedom by tuning the sp2/sp3 ratio as compared to the conventional group ІⅤ amorphous semiconductors. We report the obse- rvation of large magnetic circular dichroism (MCD) in Co doped a-C films. While as-grown films exhibit a small MCD signal, broad MCD spectra with large amplitude of 30 kdeg/cm are observed for the films after 600oC rapid thermal annealing (RTA). The X-ray photoelectron spectr- oscopy measurement and Raman spectra results support the appearance of the large MCD effect strongly depends on the sp2 /sp3 and Co dopants. It might be originated from the interaction of Co nanocrystals and a-C host and can be useful for magneto-optical application.