Computational design of spin-caloric nanosructures

自旋热量纳米结构的计算设计

• 批准号: 198010637
• 负责人: Privatdozent Dr. Phivos Mavropoulos
• 金额: --
• 依托单位: PGI-1 / IAS-1: Quanten-Theorie der Materialien
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/198010637?language=en
• 关键词: Computational; design; spin; caloric; nanosructures; Computational; design; spin; caloric; nanosructures

Modern information technology is based to a great extent on nanometer-sized magnetic systems. Information is stored in magnetic nanostructures that reside on hard disks or in magnetic memories. This information is read-out, and in many cases written-in, by spin-polarized currents, i.e., electrical currents carrying a magnetization. These currents inevitably contribute to heat production and heat transport, summarized with the term “caloric effects.” The inverse phenomenon, i.e. the creation of a spin-polarized electron current due to a heat current that is forced by a temperature gradient, is inevitable as well. We therefore face a coupling between the charge, spin, and heat current in these systems. Such phenomena depend strongly on the type of material, but they also depend on the nanostructure size and geometry because of an effect known as quantum confinement. This is basically caused by the reflection of electrons at the nanostructure boundaries and crucially affects the density of quantum levels of the system. Here we propose a theoretical and computational study of the coupling of charge, spin and heat currents in nanostructured systems, analyzing and possibly optimizing the influence of material type and structure parameters. The study will take place with state-of-the-art quantummechanical methods. We anticipate that at the end of the funding period we will understand how to tune the spin-caloric transport properties of nanostructures to values that are desired for application.

现代信息技术在很大程度上基于纳米尺寸的磁系统。信息存储在位于硬盘或磁性记忆中的磁性纳米结构中。这些信息是读出的，在许多情况下，通过自旋极性电流（即带有磁化强度的电流）写入。这些电流不可避免地有助于加热和热传输，总结了“热量效应”一词。反现象，即由于温度梯度强迫的热电流而导致自旋极化电子电流的产生也是不可避免的。因此，我们在这些系统中的电荷，自旋和热电流之间建立耦合。这种现象在很大程度上取决于材料的类型，但是由于量子约束的作用，它们也取决于纳米结构的大小和几何形状。这基本上是由于电子在纳米结构边界的反射而引起的，并且至关重要。影响系统量子水平的密度。在这里，我们提出了一项理论和计算研究，对纳米结构系统中电荷，自旋和热电流耦合的耦合，对材料类型和结构参数的影响进行分析并进行优化。该研究将使用最先进的量子力学方法进行。我们预计，在资金期结束时，我们将了解如何将纳米结构的自旋 - 旋转传输特性调整到适用于应用所需的值。