Spin-Orbit and Magnetic Scattering and Non-Equilibrium Properties by Weak Localization

利用薄金属膜中电子的弱局域化， 观察电子散射从杂质原子所产生的自旋- 轨道和磁性电子-杂质原子相互作用。 运输 作为施加磁场的函数测量的数据可以 解释产生的电子结构的信息， 杂质原子。 早期对S和P杂质的研究是 被扩展和延伸以包括d杂质。 额外 子项目将研究薄膜的影响下， 高电流密度。 这对应于一个稳定的非平衡态 电子温度远高于声子的状态 温度 这样的测量产生关于 电子-声子系统，电子-声子相互作用和 薄膜和衬底之间的Kapitza电阻。 %%% 由于量子效应，金属中的电子表现出 粒子和波的性质。 在低温下，电子 波在很长的距离上是相干的， 金属的特性。 特别是，传输特性 因为电子波可以 互相干扰。 外部磁场改变了 相位的电子波和修改的干扰。 作为 因此电阻取决于磁场。 （对于 由于历史原因，这种现象被称为弱本地化）。 对磁阻的仔细分析揭示了 关于电子的命运作为时间的函数的信息。 例如，我们可以确定电子自旋的旋转为 在皮秒的极短时间尺度上的时间函数 (one百万分之一秒）。 这样的旋转发生在 当电子遇到杂质时，称为自旋轨道 散射 这种散射正在研究各种杂质 原子（铜、锌、金、锡等）在主体镁金属中。 的 研究提供了有关磁场和 金属和合金的电子特性，并将有助于 开发具有有用特性的新材料，特别是 在低温下。

Weak localization of electrons in thin metal films is used to observe electron scattering from impurity atoms arising from spin- orbit and magnetic electron-impurity atom interactions. Transport data measured as a function of an applied magnetic field can be interpreted to yield information about the electronic structure of the impurity atoms. Earlier research on s and p impurities is being expended and extended to include d impurities. An additional subproject will investigate thin films under the influence of a high current density. This corresponds to a steady non-equilibrium state with the electron temperature considerably above the phonon temperature. Such measurements yield information about the electron-phonon system, the electron-phonon interaction and the Kapitza resistance between film and the substrate. %%% Because of quantum effects, electrons in metals display both particle and wave properties. At low temperatures, the electron waves are coherent over extended distances and influence the properties of the metal. In particular, the transport properties such as the resistance are modified because the electron waves can interfere with each other. An external magnetic field alters the phase of the electron waves and modifies the interference. As a consequence the resistance depends on the magnetic field. (For historical reasons, this phenomena is called weak localization). A careful analysis of the magneto-resistance reveals detailed information about the fate of the electrons as a function of time. For example, we can determine the rotation of the electron spin as a function of time on the very short time scale of pico-seconds (one millionth of a millionth of a second). Such a rotation occurs when the electron encounters impurities and is called spin-orbit scattering. This scattering is being studied for various impurity atoms (copper, zinc, gold, tin, etc.) in host magnesium metal. The research provides important information about the magnetic and electronic properties of metals and alloys and will aid in the development of new materials with useful properties, particularly at low temperatures.