Localized electronic states at grain boundaries on the surface of graphene and graphite

Recent advances in large-scale synthesis of graphene and other 2D materials have underscored the importance of local defects such as dislocations and grain boundaries (GBs), and especially their tendency to alter the electronic properties of the material. Understanding how the polycrystalline morpho...

Full description

Bibliographic Details
Authors: Luican-Mayer, Adina, Barrios Vargas, José Eduardo|||0000-0002-6880-8941, Falkenberg, Jesper Toft, Autès, Gabriel, Cummings, Aron|||0000-0003-2307-497X, Soriano, David|||0000-0003-2358-526X, Li, Guohong, Brandbyge, Mads|||0000-0002-0126-9824, Yazyev, Oleg V.|||0000-0001-7281-3199, Roche, Stephan|||0000-0003-0323-4665, Yandrei, Eva Y.
Format: article
Publication Date:2016
Country:España
Institution:Universitat Autònoma de Barcelona
Repository:Dipòsit Digital de Documents de la UAB
Language:English
OAI Identifier:oai:ddd.uab.cat:199184
Online Access:https://ddd.uab.cat/record/199184
https://dx.doi.org/urn:doi:10.1088/2053-1583/3/3/031005
Access Level:Open access
Keyword:Grain boundaries
Graphene
Scanning tunneling microscopy
Scanning tunneling spectroscopy
Description
Summary:Recent advances in large-scale synthesis of graphene and other 2D materials have underscored the importance of local defects such as dislocations and grain boundaries (GBs), and especially their tendency to alter the electronic properties of the material. Understanding how the polycrystalline morphology affects the electronic properties is crucial for the development of applications such as flexible electronics, energy harvesting devices or sensors.Wehere report on atomic scale characterization of several GBs and on the structural-dependence of the localized electronic states in their vicinity. Using low temperature scanning tunneling microscopy"Q and spectroscopy, together with tight binding and ab initio numerical simulations we explore GBs on the surface of graphite and elucidate the interconnection between the local density of states and their atomic structure.Weshow that the electronic fingerprints of these GBs consist of pronounced resonances which, depending on the relative orientation of the adjacent crystallites, appear either on the electron side of the spectrum or as an electron-hole symmetric doublet close to the charge neutrality point. These two types of spectral features will impact very differently the transport properties allowing, in the asymmetric case to introduce transport anisotropy which could be utilized to design novel growth and fabrication strategies to control device performance.