［Fe／Cr］多层膜及掺入Si中介层后的层间耦合和磁电阻效应

INTERLAYER COUPLING AND MAGNETORESISTANT EFFECT IN THE MULTILAYERS DOPED WITH Si LAYERS

用真空蒸镀方法制备了［Ｆｅ／Ｃｒ］，［Ｆｅ／Ｃｒ／Ｓｉ］和［Ｆｅ／Ｓｉ］多层膜．研究了Ｃｒ层、Ｓｉ层和Ｃｒ＋Ｓｉ层厚度变化对层间耦合和磁电阻的影响．Ｆｅ层厚为２ｎｍ，Ｃｒ层厚度变化存在耦合振荡和巨磁电阻及其振荡．磁电阻值为１４６％（４２Ｋ）．在Ｃｒ层中加入一半Ｓｉ层或全部由Ｓｉ层替代，振荡消失，磁电阻减小到千分之几．根据掺Ｓｉ层后多层膜的电阻率变化，认为Ｓｉ加入使非磁层中自由电子数减少，随之极化效应也变弱，导致振荡消失。

and multilayered systems were prepared by the vacuum evaporating method. The effects of the altered space thicknesses of the nonmagnetic Cr,Si and Cr+Si layers on the exchange coupling and the magneto resistance of those multilayers were studied. The Fe layers were fixed on 2.0nm. The oscillation of the interlayer coupling and the giant magnetoresistance (GMR) and its oscillation with the change of the Cr layer thickness were observed. The GMR was 14.6% at 4.2K. There was no oscillatory effect of the exchange coupling and GMR in the and multilayers was found. According to the increases of the resistivity of the samples doped with Si layers,we believe the conducting electrons in the nonmagnetic layers should decrease largely. This would be the cause to reduce the polarization effect of those electrons in the space layers. Then the oscillatory exchange coupling disappeared and the magnetoresistance was much reduced.