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QuantumWise CEO, Prof. Kurt Stokbro, will give an invited talk at the European Nanometrology Workshop 19-20 November 2009 in Braunschweig, Germany.

Conference website

Abstract

When the minimum feature size of a system approaches the atomic scale, the electrical properties of the system can no longer be described using classical concepts like drift and diffusion of electrons. In this talk I will review the classical description of Ohmic transport and present a new bottom up approach to electrical transport based on a quantum mechanical description that takes into account the atomic scale geometry of the system. The electrons are described with a full atomic-scale Hamiltonian and the electron transport equations are solved in terms of Non-Equilibrium Greens Functions (NEGF)[1]

The methodology has been implemented in the Atomistix ToolKit (ATK) from QuantumWise [2], which has become the de facto standard for modeling of the electrical properties of nano-scale systems and there are now many hundred publications with applications of the method. ATK can describe the system from first principles using Density Functional Theory[3] or by semi-empirical methods. The modeling of the nanostructure can be combined with a continuum description of dielectric regions and electro-static gates[4] allowing for multi-scale modeling of the system.

A number of application examples will be presented, including electrical properties of Graphene, Carbon nanotubes, Spintronics, Molecular devices, semi-conductor nanowires and interfaces. The focus will be on systems relevant for metrology applications.

References:

1. K. Stokbro First Principles modeling of electron transport, J. of Physics Cond. Mat. 20, 064216 (2008).
2. http://www.quantumwise.com
3. Mads Brandbyge, Jose-Luis Mozos, Pablo Ordejon, Jeremy Taylor, and Kurt Stokbro, Density functional method for nonequilibrium electron transport, Phys. Rev. B. 65, 165401 (2002).
4. H. H. B. Sørensen, P.C. Hansen, D.E.Petersen, S. Skelboe and K. Stokbro, Efficient wave function matching approach for quantum transport calculations, Phys Rev. B 79, 205322 (2009).
5. Y. J. Lee, M. Brandbyge, J. Puska, J. Taylor, K. Stokbro and R. M. Nieminen, Electron transport through monovalent atomic wires, Phys Rev. B 69, 125409 (2004)