单分子磁体自旋电子器件的界面效应研究

项目名称： 单分子磁体自旋电子器件的界面效应研究

项目编号： No.11274238

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 周丽萍

作者单位： 苏州大学

项目金额： 78万元

中文摘要： 单分子磁体由磁性中心离子和有机配体组成，通过对配体基团进行修饰，易将单分子磁体嫁接到材料表面或电极上，探索其作为自旋阀、自旋晶体管、多量子点器件的研究。器件中金属电极和有机分子基团接触界面的构形和特性对电子自旋的注入和输运起至关重要的作用，是目前分子自旋电子器件的研究重点。本项目将应用量子力学的多尺度方法，将非平衡格林函数方法与第一性原理、紧束缚模型等结合起来，深入系统地研究基于单分子磁体的自旋电子器件中的界面效应。重点研究单分子磁体化学吸附情况下自旋极化率的改变机制：包括界面处金属电极与有机磁性材料复杂相互作用对分子能级自旋相关的展宽和移动，对电极表面磁性的改变；金属/有机分子界面形成自旋相关杂化态对注入自旋极化率大小和方向及输运的调制；分子自身磁性因素的调控及对器件自旋输运的影响。寻找分子器件自旋输运增强的途径，探索新的功能性器件界面结构设计，实现自旋器件特定性能在分子尺度上有效调控。

中文关键词： 单分子磁体；金属/有机分子界面；自旋输运；分子自旋电子器件；密度泛函理论

英文摘要： Compounds of the single-molecule magnet (SMM) class consist of an inner magnetic core with a surrounding shell of organic ligands. They are now considered as promising candidates for molecular spintronic devices, such as molecular spin-walve, molecular spin transistors and molecular multidot devices, since their structures can be easily tailored through playing with the anchoring groups and grafted to the surface of the metal electrodes. The mechanisms underlying the spin injection and spin transport process across the metal/organic interface are still to be unraveled and remain one of the most important challenges in this new uprising field. We foucus on the interface effects in single-molecule magnets based spintronic devices，and expect to reveal the role of the interface for spin injection into SMMs of the devices,by using the multi-scale methods,the density functional theory and nonequilibrium Green's function techniques,as well as the tight binding models.We aim to point out the dominating mechanisms of how the electron spin polarization transforms as the SMMs connect to the metal electrode by chemical adsorption,to disclose how the complex interaction between the organic magnetic molecules and the metal electrodes spin-dependently broaden and move the molecule energy levels, to understand how the adsor

英文关键词： single-molecule magnet；metal/organic interface；spin transport；molecular spintronics；density functional theory