Spin tropism relative to regional magnetization vector will affect its transporting property . the discovery of gmr effect pioneered the new subject which is called magnetoelectronics 自旋相对于局域磁化矢量的取向将影响其输运性质，巨磁电阻效应的发现开辟了磁电子学这一新的学科和研究领域。
In this composite , it is observed that a maximum mr value reaches 9 . 2 % at t = 77k when p approaches increasingly pc . it is proposed that mr effect may depend on microstructure near m - i phase transition 2 ， t 77k人这进一步表明在金属一绝缘体相变附近的微观结构对磁电阻效应产生重大的影响。
( 1 ) mr and percolation effect : a new microstructure is observed due to size of the tio2 particle much more than that of the cro2 particle , and obviously different shapes Tio 。颗粒的粒径比cro 。大得多，形状为球形，这两种颗粒复合形成一类新的微结构，以降低ctoz渗流阈值浓度，提高低场磁电阻。
