Efeito do campo elétrico em nanocones formados por aln e BN: um estudo por primeiros princípios

The development of computers and algorithms capable of making increasingly accurate and rapid calculations as well as the theoretic foundation provided by quantum mechanics has turned computer simulation into a valuable research tool. The importance of such a tool is due to its success in describing...

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Bibliographic Details
Author: Pedreira, Danilo Oliveira
Format: master thesis
Status:Published version
Publication Date:2011
Country:Brasil
Institution:Universidade Federal do Rio Grande do Norte (UFRN)
Repository:Repositório Institucional da UFRN
Language:Portuguese
OAI Identifier:oai:repositorio.ufrn.br:123456789/18590
Online Access:https://repositorio.ufrn.br/jspui/handle/123456789/18590
Access Level:Open access
Keyword:Nanocones
Campo elétrico
CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
Description
Summary:The development of computers and algorithms capable of making increasingly accurate and rapid calculations as well as the theoretic foundation provided by quantum mechanics has turned computer simulation into a valuable research tool. The importance of such a tool is due to its success in describing the physical and chemical properties of materials. One way of modifying the electronic properties of a given material is by applying an electric field. These effects are interesting in nanocones because their stability and geometric structure make them promising candidates for electron emission devices. In our study we calculated the first principles based on the density functional theory as implemented in the SIESTA code. We investigated aluminum nitride (AlN), boron nitride (BN) and carbon (C), subjected to external parallel electric field, perpendicular to their main axis. We discuss stability in terms of formation energy, using the chemical potential approach. We also analyze the electronic properties of these nanocones and show that in some cases the perpendicular electric field provokes a greater gap reduction when compared to the parallel field