Dynamical properties of nanostructured Ferromagnet - Diluted Magnetic Semiconductor Hybrids

我们打算开发新型的铁磁-半导体杂化纳米结构，并在较宽的时间范围内研究其动力学性质。我们的想法是使用稀释的磁性半导体，在这种半导体中，离子矩产生巨大的g因子，即使在相邻铁磁的相对较弱的杂散场中，也会导致光学性质的实质性变化。DMS的光学特征将作为纳米磁铁的磁性及其动力学行为的探针。我们打算使用强光激发通过电流注入或热加热来进行场调制，并获得关于前向响应、瞬时FM-DMS耦合以及自旋-晶格弛豫的信息。相反，调频导线和调频网点的杂散场将被用来通过巨塞曼效应来控制DMS中的横向自旋分布。我们将阐明自旋输运的长度和时间尺度、自旋相干性和磁化动力学，这些对于获得半导体自旋纳米结构具有重要的基础价值。我们的研究将使我们能够评估这种混合结构在没有外加磁场的情况下横向选择性自旋注入半导体的潜力。

We intend to develop novel ferromagnet-semiconductor hybrid nanostructures and to study their dynamical properties in a wide time range. Our idea is to use a diluted magnetic semiconductor, where the ionic moments give rise to giant g-factors providing substantial changes in the optical properties, even in the relatively weak stray field of an adjacent ferromagnet. The optical features of the DMS will serve as a probe for the magnetic properties of the nanomagnets and their dynamical behavior. We intend to use intensive optical excitation for field modulation via current injection or thermal heating and to gain information about the preccesional response, the transient FM-DMS coupling as well as spin-lattice relaxation. Conversely, the stray field of the FM wires and dots will be utilized to manipulate the lateral spin distribution in the DMS via the giant Zeeman effect. We will be elucidating the length and times scales of spin transport, the spin coherence and the magnetization dynamics, values of fundamental importance for achieving semiconductor spin nanostructures. Our studies will allow us to evaluate the potential of the hybrid structures for laterally selective spin injection into a semiconductor without external magnetic field.