Publication Date

2012

Document Type

Thesis

Committee Members

Amir Abbas Farajian (Advisor), Hong Huang (Committee Member), Sharmila Mukhopadhyay (Committee Member)

Degree Name

Master of Science in Engineering (MSEgr)

Abstract

Graphene nanoribbons (GNRs) constitute a new class of nanostructured materials with unique properties and significant potential for applications. During production of GNRs, defects are generally introduced within the lattice. Assessment of defects' stability and characterization of their effects on GNRs are therefore very important for predicting GNRs performance under realistic circumstances. Here we consider various possible defects, namely the ones caused by removal/addition of carbon atoms from/to the lattice as well as those caused by bond rotation/rearrangement. Our study is based on ab initio geometry optimization and electronic structure calculations. We determine which defects can be stable in graphene nanoflakes and/or GNRs, by calculating the corresponding vibration modes. We further investigate how the presence of defects would modify electronic transport through defected GNRs. Among the defects considered, only some turn out to be stable within the GNR lattice. Transport in presence of defects is generally less compared to the pristine case, however, different defects cause different levels of conductance reduction. We also investigate the effects of a spin-polarized defect on transport characteristics.

Page Count

98

Department or Program

Department of Mechanical and Materials Engineering

Year Degree Awarded

2012


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