Peierls Instability and Spin Orderings of Ultranarrow Graphene Nanoribbons in Graphane

Narrow graphene nanoribbons are a promising channel material for field-effect transistors. Here, using first-principles density functional calculations, we investigate the competition between Peierls instability and spin orderings in zigzag graphene nanoribbons carved in a fully hydrogenated graphen...

Full description

Saved in:
Bibliographic Details
Published in:Journal of physical chemistry. C 2012-06, Vol.116 (25), p.13795-13799
Main Authors: Kim, Hyun-Jung, Oh, Sangchul, Zeng, Chaggan, Cho, Jun-Hyung
Format: Article
Language:English
Subjects:
Applied sciences
Condensed matter: electronic structure, electrical, magnetic, and optical properties
Condensed matter: structure, mechanical and thermal properties
Cross-disciplinary physics: materials science
rheology
Electron states
Electronics
Equations of state, phase equilibria, and phase transitions
Exact sciences and technology
Fullerenes and related materials
diamonds, graphite
Materials science
Methods of electronic structure calculations
Physics
Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
Specific materials
Specific phase transitions
Structural transitions in nanoscale materials
Transistors
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Narrow graphene nanoribbons are a promising channel material for field-effect transistors. Here, using first-principles density functional calculations, we investigate the competition between Peierls instability and spin orderings in zigzag graphene nanoribbons carved in a fully hydrogenated graphene (graphane) as a function of their width N (the number of zigzag C chains composing a nanoribbon). We find that such a nanoribbon with N = 1 undergoes a Peierls instability caused by a strong electron–lattice coupling, leading to a band-gap opening. For N ≥ 2, the Peierls instability is significantly weakened or disappears because of the interaction of zigzag C chains, whereas a ferromagnetic spin ordering on each side is stabilized by the formation of the localized edge states. We find that the spins on both sides are further stabilized with their antiparallel alignments, accompanying the band gap opening. Therefore, ultranarrow zigzag graphene nanoribbons carved in graphane are semiconducting as a consequence of a Peierls instability or an antiferromagnetic spin ordering between the two edges which is useful for the application of field-effect transistors.
ISSN:1932-7447
1932-7455
DOI:10.1021/jp302733p