Influence of the Composition on the Magnetotransport Mechanism in the Magnetoresistive Composites

• Main Authors: Chen-cheng Lin, 林宸澂
• Other Authors: Jen-bin Shi
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/93692539019456993929

碩士 === 逢甲大學 === 電子工程所 === 95 === This study discussed the influence of magnetoresistance/metal and magnetoresistance/oxide on the magnetotransport behavior and also researched in the magnetic composites, the inter-grain carrier magneto-transport behaviors in these nearly spin polarization hetero-structural composites are investigated either. In low temperature and dimension of samples, the transport of carriers is affected markedly by the quantum interference and surface effect. While the size of grain approaching nanometer scale, the effects of mesoscopic physics including columb interaction, double interaction, tunneling effect and carrier hopping behavior will be different. Various compositions of A/B magnetic manganite oxide composites will be synthesized to study the boundary effect on the magnetic-electric interaction by the measurements of temperature-dependent resistivity, low field FC-ZFC magnetization and magnetic hysteresis with various applied field. Then various compositions of composites to modulate the spin polarization condition in the grain boundary and observe the behavior of the temperature dependence of transport carrier hopping across grain boundary.