Mossbauer Studies of Advanced Superconducting Materials

金博尔教授将使用穆斯堡尔谱学研究含有少量铁的超导系统的晶格动力学。3d过渡元素对超导和磁性的影响将被确定。高温氧化物超导体中的振动态将被用稀土离子取代Y和用锡或离子取代铜来探索。当铁含量达到临界值时，晶格由正交相转变为四方相。用穆斯堡尔谱和中子衍射法描述了这些化合物的相间氧阴离子有序-无序转变，并观察了无序相中的磁性行为。BaPb1-xBicO3超导体的中子衍射测量将继续进行，寻找氧化物和硫化物的其他高温超导材料也将继续进行。

Professor Kimball will investigate the lattice dynamics of superconducting systems containing small concentrations of iron using Mossbauer spectroscopy. The influence of the 3d transition elements on superconducting and magnetic properties will be determined. Vibrational states in the high temperature oxide superconductors will be probed with substitutions of rare earth ions for yttrium and of tin or ion for copper. At a critical iron concentration the lattice transforms from orthorhombic to tetragonal. Mossbauer and neutron diffraction will be used to delineate the oxygen anion order-disorder transformation between phases of these compounds and to observe the magnetic behavior in the disordered phase. Neutron diffraction measurements in the BaPb1-xBicO3 superconductors will continue as will a search for other high temperature superconducting materials of the oxides and sulphides.