Electronic resonance states in metallic nanowires during the breaking process simulated with the ultimate jellium model

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Journal Title
Journal ISSN
Volume Title
School of Science | A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2003
Major/Subject
Mcode
Degree programme
Language
en
Pages
075417/1-11
Series
Physical Review B, Volume 67, Issue 7
Abstract
We investigate the elongation and breaking process of metallic nanowires using the ultimate jellium model in self-consistent density-functional calculations of the electronic structure. In this model the positive background charge deforms to follow the electron density and the energy minimization determines the shape of the system. However, we restrict the shape of the wires by assuming rotational invariance about the wire axis. First, we study the stability of infinite wires and show that the quantum-mechanical shell structure stabilizes the uniform cylindrical geometry at the given magic radii. Next, we focus on finite nanowires supported by leads modeled by freezing the shape of a uniform wire outside the constriction volume. We calculate the conductance during the elongation process using the adiabatic approximation and the WKB transmission formula. We also observe the correlated oscillations of the elongation force. In different stages of the elongation process two kinds of electronic structures appear: one with extended states throughout the wire and one with an atom-cluster-like unit in the constriction and with well-localized states. We discuss the origin of these structures.
Description
Keywords
ultimate jellium, density functional theory, nanowires, multigrid methods
Other note
Citation
Ogando, E. & Torsti, T. & Zabala, N. & Puska, Martti J. 2003. Electronic resonance states in metallic nanowires during the breaking process simulated with the ultimate jellium model. Physical Review B. Volume 67, Issue 7. 075417/1-11. ISSN 1550-235X (electronic). DOI: 10.1103/physrevb.67.075417.