Spin polarized currents in superconductor-ferromagnet and antiferromagnet-ferromagnet heterostructures

该项目的主要目标是研究具有不同类型有序参数的材料的快速过程，例如，超导性（SC）和电荷或自旋密度波（相应地，CDW和SDW），以及由这些材料组成的纳米结构。在过去的几年里，由于使用几百甚至几十飞秒量级的时间分辨率的测量技术和方法的发展，对研究这些过程的兴趣急剧上升。基于发展的理论方法（Keldysh绿色函数方法），我们计划研究不同类型的序参量在它们可能共存的系统中的动力学（即，在最近发现的磷属元素化物-超导体中，在铜酸盐中等），以及在混合结构中，如超导体-铁磁体、超导体-（自旋密度波材料）和其他组合。我们将描述所涉及的序参数的时间演化，例如，在通过激光脉冲刺激系统之后。我们还计划计算超导体-铁磁体-超导体、超导体-（自旋密度波材料）-超导体和其他组合形式的类约瑟夫森结中的非稳态约瑟夫森和自旋电流。本项目计划的研究和结果不仅从基础研究的角度来看，而且可能有许多应用。自旋电子学领域的现代设备的基础上的磁性和超导材料和异质结构，和短时间的过程是一个例子。

The main objectives of the project is study of fast processes in materials with order parameters of different types, e.g., superconductivity (SC) and charge- or spin-density wave (CDW and SDW, correspondingly), and in nanostructures composed of such materials. The interest in studying these processes has drastically arisen in the last years as a result of the development of technology and methods of measurement using time resolution of the order of several hunreds or even tens femtoseconds. On the basis of the developed theoretical methods (Keldysh Green functions approach) we plan to investigate the dynamics of order parameters of different types in systems where they may coexist (i.a., in recently discovered pnictide-superconductors, in cuprates, etc.), and also in hybrid structures like superconductor-ferromagnet, superconductor-(spin-density wave material) and other combinations.We will describe time evolution of the order parameters involved, e.g., after a stimulation of the system by a LASER pulse. We plan to calculate also non-stationary Josephson and spin currents in Josephson-like junctions of the form superconductor-ferromagnet-superconductor, superconductor-(spin-density wave material)-superconductor and other combinations.The research and results planned in this project are of great interest not only from the perspective of fundamental research but they may have numerous applications. The field of spintronics with modern devices based on magnetic and superconducting materials and heterostructures, and short time processes is one of examples.