石墨带超导结的电子输运特性研究

项目名称： 石墨带超导结的电子输运特性研究

项目编号： No.11274059

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： 汪军

作者单位： 东南大学

项目金额： 78万元

中文摘要： 自从单层石墨成功制备以来，它就吸引了人们广泛的研究兴趣。石墨超导结是研究电子的相对论性质和超导电性相互作用的重要场所，而作为石墨器件的基本单元石墨带也展现了一些大块单层石墨不具有的物理性质。本项目主要研究拉链型石墨带的电子赝宇称性质对超导电性的物理影响。通过研究不同偶数型和奇数型拉链石墨带超导结的电导和约瑟夫森超流特性，以及他们对各种外界参数的响应特征，包括不同的势场和结构形状，来进一步揭示拉链石墨带中的电子赝宇称的物理本质以及它对库珀对输运的影响；并探索非磁性的拉链石墨带pi态超导结和库珀对空间分离器件。这个项目的研究将对理解相对论电子的超导电性特征以及为利用拉链型石墨带的赝宇称性质制造石墨超导电子器件打下一定的理论基础。

中文关键词： 石墨；超导；约瑟夫森结；谷自由度；输运性质

英文摘要： Since successful implementation of a single atom-layer of carbon in experiments, graphene has attracted tremendous attentions and interests of researchers because of its special electronic band structure and excellent physics properties. Graphene-superconductor junction is an ideal arena for interplay of the realistic Dirac fermions and superconductivity, and meanwhile graphene-nanoribbons exhibit peculiar physical properties different from the bulk graphene. In this proposal, we will investigate the effect of the electron pseudoparity on superconductivity in a zigzag graphene nanoribbon. By studying the conductance and supercurrent properties of different superconductor-ribbon junctions as well as the effect of system parameters including the potential landscapes and junction configurations, we will explore the physics origin of the electron pseudoparity in the zigzag graphene nanoribbon and devise possible nonmagnetic pi-state superconductor junction and the spatial Cooper-pair splitter. The proposal is expected to shed light on devising the superconducting electronic devices based on graphene nanoribbons and understanding the characteristic of superconductivity of Dirac Fermions.

英文关键词： graphene；superconductor；josephson junction；valley degree of electron；transport property