双层石墨烯中异常电阻行为的观察

Observation of Anomalous Resistance Behavior in Bilayer Graphene.

作者信息

Liu Yanping, Lew Wen Siang, Liu Zongwen

机构信息

Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA.

School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.

出版信息

Nanoscale Res Lett. 2017 Dec;12(1):48. doi: 10.1186/s11671-016-1792-z. Epub 2017 Jan 17.

DOI:10.1186/s11671-016-1792-z

PMID:28097601

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5241263/

Abstract

Our measurement results have shown that bilayer graphene exhibits an unexpected sharp transition of the resistance value in the temperature region 200~250 K. We argue that this behavior originates from the interlayer ripple scattering effect between the top and bottom ripple graphene layer. The inter-scattering can mimic the Coulomb scattering but is strongly dependent on temperature. The observed behavior is consistent with the theoretical prediction that charged impurities are the dominant scatters in bilayer graphene. The resistance increase with increasing perpendicular magnetic field strongly supports the postulate that magnetic field induces an excitonic gap in bilayer graphene. Our results reveal that the relative change of resistance induced by magnetic field in the bilayer graphene shows an anomalous thermally activated property.

摘要

我们的测量结果表明，双层石墨烯在200~250 K的温度范围内呈现出电阻值意外的急剧转变。我们认为这种行为源于顶部和底部波纹石墨烯层之间的层间波纹散射效应。这种相互散射可以模拟库仑散射，但强烈依赖于温度。观察到的行为与理论预测一致，即带电杂质是双层石墨烯中的主要散射源。随着垂直磁场增加电阻增大，有力地支持了磁场在双层石墨烯中诱导出激子能隙的假设。我们的结果表明，双层石墨烯中磁场诱导的电阻相对变化呈现出反常的热激活特性。