| Summary: | 碩士 === 國立中正大學 === 物理系 === 87 === The transition metal oxides exist rich electromagnetic property. This kind of films both have theorical and applicated intresting, and focus on Fe、Co、Ni. We extend the study to Mm3O4 and MnO. High quality single-crystalline films of Mm3O4 and MnO are grown on single crystal substrate by plasma-oxygen-assisted molecular beam epitaxy, respectively at different growth temperature, 2500C and 8000C. The Mn3O4 is ferrimagnetism and MnO is antiferromagnetism. By using in-situ reflection high energy electron diffraction (RHEED) to observe the epilayer surface, and X-ray q-2q diffraction to characterize the structure. From these results we can obviously discover that different growing temperature affect the epitaxy result. Besides, we used SQUID to measure the magnetic property of these samples by applying maximum magnetic field~5 tesla at T=5K, 20K. The TC of Mn3O4 is measured about 49K which is ~7K higher than the bulk value. And the MnO sample, we find that there maybe still a little impurity Mn3O4 inside. But this didn't reveal in X-ray diffraction result.
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