中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Effect of electron-hole inhomogeneity on specular Andreev reflection and Andreev retroreflection in a graphene-superconductor hybrid system

文献类型:期刊论文

作者Cheng, SG ; Zhang, H ; Sun, QF
刊名PHYSICAL REVIEW B
出版日期2011
卷号83期号:23
关键词TRANSPORT COLLOQUIUM SCHEME PHASE
ISSN号1098-0121
通讯作者Cheng, SG: NW Univ Xian, Dept Phys, Xian 710069, Peoples R China.
中文摘要The electron-hole inhomogeneity in graphene has been confirmed to be a new type of charge disorder by recent experiments, and the largest energy displacement of electron and hole puddles with respect to the Dirac point can reach nearly 30 meV. Here we focus on how the electron-hole inhomogeneity affects the specular Andreev reflection as well as the Andreev retroreflection. In a four-terminal graphene-superconductor hybrid system, we find that the Andreev coefficients can hardly be affected even under a rather large electron-hole inhomogeneity (typically 30 meV), and the boundary distinguishing two Andreev reflections can well hold, although the strength of the charge puddles, W = 30 meV, is much larger than the superconductor gap, Delta = 1 meV. Furthermore, when charge puddles are two orders of magnitude larger than the superconductor gap, a specific kind of Andreev reflection can still be obviously detected. To quantitatively describe what degree of the boundary is blurred, a quantity D is introduced which measures the width of a crossover region between specular Andreev reflection and retroreflection in energy space. We confirm that the boundary blurring is much smaller than the charge puddle strength W. In addition, we study the effect of Anderson disorder for comparison, and we find that the boundary is held much more obviously in this case. Finally, the fluctuations of the Andreev reflection coefficient are studied. Under a typical experimental charge puddle, the fluctuations are very small when the energy of the particles is away from the boundary, again confirming that the retroreflection and specular reflection can be clearly distinguished and detected in the presence of the electron-hole inhomogeneity.
收录类别SCI
资助信息NSF-China [10974236, 11004159, 11074174]; Natural Science Basic Research Plan in the Shaanxi Province of China [2010JQ1007]
语种英语
公开日期2013-09-17
源URL[http://ir.iphy.ac.cn/handle/311004/36416]  
专题物理研究所_物理所公开发表论文_物理所公开发表论文_期刊论文
推荐引用方式
GB/T 7714
Cheng, SG,Zhang, H,Sun, QF. Effect of electron-hole inhomogeneity on specular Andreev reflection and Andreev retroreflection in a graphene-superconductor hybrid system[J]. PHYSICAL REVIEW B,2011,83(23).
APA Cheng, SG,Zhang, H,&Sun, QF.(2011).Effect of electron-hole inhomogeneity on specular Andreev reflection and Andreev retroreflection in a graphene-superconductor hybrid system.PHYSICAL REVIEW B,83(23).
MLA Cheng, SG,et al."Effect of electron-hole inhomogeneity on specular Andreev reflection and Andreev retroreflection in a graphene-superconductor hybrid system".PHYSICAL REVIEW B 83.23(2011).

入库方式: OAI收割

来源:物理研究所

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