Construction of an automatic MOKE system and analysis of magnetic hysteresis measured on nanostructures

• Main Authors: Shu-Fan Yeh, 葉書帆
• Other Authors: Yue-Lin Huang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/36613690855382806210

碩士 === 國立東華大學 === 應用物理研究所 === 98 === In our previous research, with SQUID measurement, we found and confirmed magnetism of Ge nano-structure with SiO2 caped behaved specially. The result is obviously different from the diamagnetism behavior of Ge bulk. Our primary goal is providing an effective measurement method with surface magnetic sensitivity by construct an automatic MOKE (Magneto-Optical Kerr Effect) system, for reviewing the physical model we set up based on the results of SQUID measurement. We are focusing in further exploration of magnetic interactions between these kinds of nano-structure, the origin of the condition causing negative coercive force, and analyzing the complex condition of magnetic dipole rotation with theoretical simulation. We have produced phase-diagrams by the relation between the magnetic interactions and the magnitude of critical magnetic field strength determined, and simulate results for discussing the influence of the interactions between magnetic domains in nano-structures hysteresis.