Ab-initio study of temperature effect and light impurities in metallic nanowires under surfaces

• Grant number: 09/16957-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2010
• End date: February 28, 2011
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Edison Zacarias da Silva
• Grantee: Edgard Pacheco Moreira Amorim
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Some experiments using scanning tunneling microscopy (STM) of metallic nanowires deposited on surfaces were identified as systems with promising technological applications in nanoelectronics, since it was understood that they behave as one dimensional electron conductors. Although, all experiments were done at temperatures between 7K and 12K. Therefore, since this is a fundamental question about the viability of technological applications of these systems, this work considers the theoretical study of the possibility of obtaining a nanoconductor at room temperature and under the influence of light impurities. For these reasons, we will use ab-initio methods with quasi-static approach to study the deposition of copper nanowires under Cu(111) and gold nanowires under Cu(110) and NiAl(110). We will consider also, copper nanowires with cobalt impurities and gold nanowires with palladium. After the characterization of pure nanowires under different surfaces, we will deposit light impurities (H, B, C, N, O, CO e S) to study their influence in the electronic structure through the comparison of electronic density of states and charge with pure nanowires. Finally, we will consider explicitly the temperature using ab-initio molecular dynamics at constant temperature, we would like to investigate how the temperature and the effect of the impurities affect the stability of these nanowires.