Propriedades eletrônicas de nanofios de SI-GE com sequenciamento de Fibonacci e radômico

• Ano de defesa: 2012
• Autor(a) principal: CORTEZ, André Hadad
• Orientador(a): AZEVEDO, David Lima
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Maranhão
• Programa de Pós-Graduação: PROGRAMA DE PÓS-GRADUAÇÃO EM FÍSICA/CCET
• Departamento: DEPARTAMENTO DE FÍSICA/CCET
• País: Brasil
• Palavras-chave em Português: Nanofios; Finonacci; Fractalidade; Ab initio
• Palavras-chave em Inglês: Nanowires; Fractality
• Área do conhecimento CNPq: Física da Matéria Condensada
• Link de acesso: http://tedebc.ufma.br:8080/jspui/handle/tede/1857

In this work we address a theoretical calculation of the electronic spectra in Si-Ge atomic chain that is arranged in a Fibonacci quasi-periodic sequence, by using semi-empirical quantum method based on Hückel extended model. We apply the Fibonacci substitutional sequences in the atomic building blocks A(Si) and B(Ge) through the in ation rule or recursion relation. In our ab initio calculations we use only a single point which is the sufi cient condition to consider all the orbitals and charge distribution across the entire system. Although the calculations presented here are more complete than the models adopted in the literature which take into account the electronic interaction, up to the second and third neighbors, an interesting property remains in their electronic spectra: the fractality (which is the main signature of this kind of system). We discuss this fractality of the spectra and we compare them with the randomic arrangement of Si-Ge atomic chain, and with previous results based on the tight-binding approximation of Schorödinger equation considering until the nearest neighbor.