扫描隧道显微镜局部控制下的悬空石墨烯中的热镜屈曲。

Thermal mirror buckling in freestanding graphene locally controlled by scanning tunnelling microscopy.

机构信息

1] Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium [2] Department of Physics, Shahid Rajaee Teacher Training University, Lavizan, Tehran 16788, Iran.

1] Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA [2] Laboratory for Physical Sciences, University of Maryland, College Park, Maryland 20740, USA.

出版信息

Nat Commun. 2014 Sep 17;5:4962. doi: 10.1038/ncomms5962.

DOI:10.1038/ncomms5962

PMID:25230052

Abstract

Knowledge of and control over the curvature of ripples in freestanding graphene are desirable for fabricating and designing flexible electronic devices, and recent progress in these pursuits has been achieved using several advanced techniques such as scanning tunnelling microscopy. The electrostatic forces induced through a bias voltage (or gate voltage) were used to manipulate the interaction of freestanding graphene with a tip (substrate). Such forces can cause large movements and sudden changes in curvature through mirror buckling. Here we explore an alternative mechanism, thermal load, to control the curvature of graphene. We demonstrate thermal mirror buckling of graphene by scanning tunnelling microscopy and large-scale molecular dynamic simulations. The negative thermal expansion coefficient of graphene is an essential ingredient in explaining the observed effects. This new control mechanism represents a fundamental advance in understanding the influence of temperature gradients on the dynamics of freestanding graphene and future applications with electro-thermal-mechanical nanodevices.

摘要

对独立石墨烯中波纹曲率的了解和控制对于制造和设计柔性电子设备是理想的，最近在这些追求中取得了进展，使用了几种先进的技术，如扫描隧道显微镜。通过偏置电压（或栅极电压）感应的静电力被用于操纵独立石墨烯与尖端（衬底）的相互作用。这些力可以通过镜面屈曲引起大的运动和曲率的突然变化。在这里，我们探索了一种替代机制，即热负荷，来控制石墨烯的曲率。我们通过扫描隧道显微镜和大规模分子动力学模拟来演示石墨烯的热镜屈曲。石墨烯的负热膨胀系数是解释观察到的效应的一个基本组成部分。这种新的控制机制代表了对温度梯度对独立石墨烯动力学的影响以及未来具有电热机械纳米器件的应用的理解的重大进展。