Investigation of Transition Metal Impurities by Weak Localization and the Anomalous Hall Effect

点击翻译按钮获取中文摘要

9509875 Bergmann This project is concerned with the magnetic properties of nd- atoms on the surface of noble metals or simple (s,p) metals. The complementary transport methods of weak localization and the anomalous Hall effect are employed. These methods detect the magnetic interaction between the magnetic impurity atoms and bulk/surface conduction electrons. The weak localization technique allows the detection of less that 10-4 of a monolayer of surface atoms, and is by a factor of 100 more sensitive than alternative detection methods. The anomalous Hall effect measurements help to determine the character of the magnetic atom, ferromagnetic or antiferromagnetic. This project addresses both experimental and theoretical aspects of the coupling between magnetic impurity atoms and conduction electrons. Sub-monolayers of 3d atoms, as well as 4d and 5d atoms such as zirconium, molybdenum, technetium, and ruthenium on metals such as silver and gold will be investigated. The results are of fundamental interest, but also have potential applications to technological areas such as the microelectronics industry. %%% The study of magnetism in thin films and on surfaces belongs to a very active area of materials research with numerous opportunities to have an impact on technology such as magnetic recording devises. Individual magnetic atoms form the simplest building blocks on magnetic structure. Such atoms will be investigated in this study using very sensitive techniques. On of these can detect less than one ten-thousandth of a single layer of magnetic atoms which are deposited on a metallic surface another technique is able to distinguish the direction of the individual magnetic moments of the deposited atoms. The experiments also probe to what extent the magnetic properties of surfaces differ from those of the bulk. ***