The superconducting spin valve and triplet superconductivity

超导自旋阀和三线态超导

• 批准号: 246730015
• 负责人: Dr. Pavel Vladimirovich Leksin
• 金额: --
• 依托单位: Institut für Festkörperforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/246730015?language=en
• 关键词: superconducting; spin; valve; triplet; superconductivity

This project is oriented on the experimental investigation of the superconducting triplet components arising in superconducting spin valve system ferromagnet/ferromagnet/ superconductor (F/F/S). The main goal of this work is to explore new effects caused by the interplay between superconductivity and ferromagnetism in F/F/S heterostructures. The novelty of this work is dictated by (i) the value of the fundamental knowledge regarding newly discovered triplet superconducting components in fabricated S/F structures and (ii) their possible application in spintronics as logical elements, valves etc. The classical methods which I propose to apply in this modern physics area can serve as a reliable source of experimental data: Ultra high vacuum (UHV) deposition method for F/F/S heterostructures preparation, SQUID and low temperature resistance measurements for magnetic and transport characterization. In order to reach the objectives of the project the following steps will be taken: (a) The high quality F/F/S structures will be prepared using UHV method. In particular these systems will have the following set of layers IrMn/F1/Cu/F2/Pb (where F1 and F2 = Fe, Ni0.8Fe0.2 or Co2Cr1-xFexAl). Note that Co2Cr1-xFexAl is a Heusler alloy. It is a challenging experimental task itself to couple this material with a conventional superconducting S layer namely Pb. For this scheme in case of need the interface F2/Pb will be stabilized by nonmagnetic metal such as Cu in order to prevent mutual mixing between F2 and Pb materials. (b) The interplay between magnetic and superconducting properties will be investigated. Our preliminary work gives ground to suppose that as a fundamental research result of this challenging project:(1) the evidence of the triplet superconducting components in F/F/S scheme will be registered and their properties will be investigated and analyzed; (2) the full on/off switching of the superconductivity due to the superconducting triplet spin valve effect can be experimentally achieved.

本计画系针对超导自旋阀系统铁磁体/铁磁体/超导体（F/F/S）中所产生的超导三重态成分进行实验研究。本工作的主要目标是探索F/F/S异质结构中超导性和铁磁性之间的相互作用所引起的新效应。这项工作的新奇是由（i）关于新发现的三重态超导组件在制造S/F结构的基础知识的价值和（ii）它们在自旋电子学中可能的应用作为逻辑元件，阀门等经典方法，我建议在这个现代物理领域应用可以作为实验数据的可靠来源：F/F/S异质结构制备的超高真空（UHV）沉积方法，磁性和输运特性的SQUID和低温电阻测量。为了实现项目目标，将采取以下步骤：（a）采用超高真空方法制备高质量的F/F/S结构。特别地，这些系统将具有以下一组层IrMn/F1/Cu/F2/Pb（其中F1和F2 = Fe、Ni0.8Fe0.2或Co2 Cr 1-xFexAl）。注意，Co2 Cr 1-xFexAl是Heusler合金。这是一个具有挑战性的实验任务本身耦合这种材料与传统的超导S层，即铅。对于该方案，在需要的情况下，界面F2/Pb将通过诸如Cu的过渡金属来稳定，以防止F2和Pb材料之间的相互混合。(b)将研究磁性和超导性之间的相互作用。我们的初步工作为这一具有挑战性的项目提供了基础性的研究成果：（1）在F/F/S方案中记录三重态超导组分的证据，并研究和分析它们的性质;（2）实验上可以实现超导三重态自旋阀效应引起的超导性的完全开/关。