NER: Interplay of Magnetism and Superconductivity at the Nanometer Scale

这是一个纳米级探索性研究（NER）奖，通过纳米级科学与工程招标提交的提案。将启动一项理论计划，探索复杂氧化物纳米结构中磁性和超导性的相互作用。由于所涉及材料的复杂性，该研究具有高度的探索性。直到最近，任何工程纳米结构的传统观点都认为，磁性应该在纳米尺度上完全破坏超导性。然而，过去一年的实验表明，在特征长度小于60纳米的氧化锰/氧化铜纳米异质结构中，磁性和超导性的共存是可能的。这与许多由传统磁体和传统超导体制成的异质结构形成鲜明对比，在这些异质结构中，超导性和磁性的相互作用已经得到了研究。在这种情况下，结论是超导性和磁性不能在纳米尺度上共存，当然也不能在40开尔文以上的温度下共存。氧化锰/氧化铜纳米结构中共存的发现导致了几个需要在纳米尺度上解决的重要知识问题。这些问题包括对基本方面的理解，如d波超导的磁邻近效应，半金属铁磁体的超导（d波）邻近效应，多层中远程超导和磁序的稳定（实验上可用于复杂氧化物），以及侧向线和量子点阵列（实验上不可用于复杂氧化物）。纳米级器件的概念也将被提出，它依赖于铜氧化物超导性和锰氧化物磁性在纳米尺度上的相互作用。其中一个这样的装置概念被称为超巨磁阻开关。超薄异质结构的研究将有助于更好地理解现有的纳米结构。这是一项纳米级探索性研究（NER）奖，奖励通过纳米级科学与工程招标提交的提案。将启动一项理论计划，探索复杂氧化物纳米结构中磁性和超导性的相互作用。由于所涉及材料的复杂性，该研究具有高度的探索性。直到最近，任何工程纳米结构的传统观点都认为，磁性应该在纳米尺度上完全破坏超导性。然而，过去一年的实验表明，在特征长度小于60纳米的氧化锰/氧化铜纳米异质结构中，磁性和超导性的共存是可能的。纳米级器件的概念也将被提出，它依赖于铜氧化物超导性和锰氧化物磁性在纳米尺度上的相互作用。其中一个这样的装置概念被称为超巨磁阻开关。超薄异质结构的研究将有助于更好地理解现有的纳米结构。* * *

This is a Nanoscale Exploratory Research (NER) award for a proposal submitted through the Nanoscale Science and Engineering solicitation. A theoretical program will be initiated to explore the interplay of magnetism and superconductivity in complex oxide nanostructures. The research is highly exploratory due to the complexity of the materials involved. Until very recently, conventional wisdom in any engineered nanostructure dictated that magnetism should completely destroy superconductivity at the nanometer scale. However, experimental efforts in the past year have shown that coexistence of magnetism and superconductivity is possible in Manganese-oxide/Cuprate-oxide nanometer scale heterostructures with characteristic length scales less than sixty nanometers. This is in sharp contrast to many heterostructures made of conventional magnets and conventional superconductors, where the interplay of superconductivity and magnetism has been studied. In this case the conclusion was that superconductivity and magnetism could not coexist at the nanometer scale , and certainly not at temperatures above forty Kelvin. The discovery of the coexistence in Manganses-oxide/Cuprate-oxide nanostructures leads to several important intellectual issues that need to be addressed at the nanometer scale. These issues include understanding of fundamental aspects like the magnetic proximity effect on d-wave superconductivity, the superconducting (d-wave) proximity effect on half-metallic ferromagnets, the stabilization of long-range superconducting and magnetic order in multilayers (experimentally available for complex oxides), and lateral wires and quantum dot arrays (not experimentally available for complex oxides).Nanoscale device concepts will also be proposed which rely on the interplay of Cuprate-oxide superconductivity and Manganese-oxide magnetism at the nanometer scale. One such device concept is called the super-colossal magneto-resistance switch . Work on ultra-thin heterostructures will lead to better understanding of nanostructures currently available. %%% This is a Nanoscale Exploratory Research (NER) award for a proposal submitted through the Nanoscale Science and Engineering solicitation. A theoretical program will be initiated to explore the interplay of magnetism and superconductivity in complex oxide nanostructures. The research is highly exploratory due to the complexity of the materials involved. Until very recently, conventional wisdom in any engineered nanostructure dictated that magnetism should completely destroy superconductivity at the nanometer scale. However, experimental efforts in the past year have shown that coexistence of magnetism and superconductivity is possible in Manganese-oxide/Cuprate-oxide nanometer scale heterostructures with characteristic length scales less than sixty nanometers.Nanoscale device concepts will also be proposed which rely on the interplay of Cuprate-oxide superconductivity and Manganese-oxide magnetism at the nanometer scale. One such device concept is called the super-colossal magneto-resistance switch . Work on ultra-thin heterostructures will lead to better understanding of nanostructures currently available. ***