Fe/Pd金属超晶格的磁性和内转换电Mssbauer谱研究

STUDIES OF THE MAGNETIC PROPERTIES AND ^(57)Fe CONV-ERSION ELECTRON MOSSBAUER SPECTRUM OF THE MATELLIC Fe/Pd SUPERLATTICES

利用真空双源蒸镀法成功地制备了Fe/Pd金属超晶格,并对其结构和磁性进行研究。发现其比饱和磁化强度在固定Pd层30不变时,随Fe层厚度减小而单调上升,这是界面处Fe对Pd的极化效应造成的,且得出0K下极化效应的等效Fe层厚度约为10;低温下σ-T关系满足Bloch的T^(3/2)定律,自旋波劲度系数随Fe层厚度减小而单调增大;居里温度则单调下降。~57Fe内转换电子Mssbauer谱(CEMS)的测量进一步证实极化效应的存在,而界面处Fe原子不存在磁性增强,也不存在“死层”效应。

The structural and magnetic properties of the two sources deposited Fe/Pd superlattices were studied. The samples were prepared by keeping the thickness of Pd layers dpd at 30A and varying dFe from 56 to 5.7A. The reduced saturation magnetization of Fe/Pd superlatti-ces, σ1 increased with the decrease of dFe this was due to the polarization effect of Pd. The effective thickness of polarization effect d was found as about 10 A at 0K. The temperature dependence of magnetization followed Bloch T3/2 law in the range of 7-300K. and the spin-wave stiffness constant B increased with the decrease of dFe The Curie temperature, Tc decreased with dFe The 57Fe conversion electron Mossbauer spectrum illustrated that the polarization effect existed among the layers, and there were no magnetic enhancing effect and 'dead layer effect' on the Fe atoms at the interfaces.