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The Virtual Nano. Lab for understanding Nanotechnologies Kurt Stokbro Atomistix A/S www. atomistix. com
“Experiment simply cannot do it alone – Theory and modeling are essential. ” “Furthermore, we need to understand the critical roles that surfaces and interfaces play in nanostructured materials ” US National Science and Technology Council The Interagency Working Group on Nano. Science, Engineering and Technology (IWGN, 1999)
AM is growing in relative importance Atomic scale modeling R&D expenditure will grow relatively much faster than expenditures for experimental research Atomistic modeling: A wave on top of the nanotechnology wave 2005: 20 % AM 80 % experiment 2005 AM R&D Expenditures: 50 % Experimental R&D Expenditures: 50 % 2035
Today’s use of software is limited and primarily for materials, chemistry and life science applications Electronics Life Sciences e ar w oft S Materials Chemicals
NANOTECHNOLOGY All sectors can benefit from software Electronics Life Sciences Nanotechnology Design Automation Software Materials Chemicals
Atomistix A/S www. atomistix. com
Founders/Managers Dr. Jeremy Taylor, Ph. D. in physics Main developer of Mc. DCAL at Mc. Gill University in Canada Co-developer of Tran. SIESTA VP (Product Development) of Atomistix Prof. Hong Guo, Ph. D. in physics Professor at Mc. Gill University Recognized researcher in the fields of charge and spin transport theory, and device modeling VP (Scientific Research) of Atomistix Incorporated November 2003 by four founders/managers Dr. Kurt Stokbro, Ph. D. in physics Professor at Niels Bohr Institute, University of Copenhagen Recognized researcher in the field of atomic scale modeling VP (Business Development) of Atomistix Dr. Thomas Magnussen: Ph. D. in chemical engineering, MBA (INSEAD) 25 years experience in science, technology and business development CEO of Atomistix
Today Atomistix A/S Mail address: Niels Bohr Institute • Rockefeller Complex • Juliane Maries Vej 30 • DK-2100 Copenhagen Office address: Henrik Harpestrengs Vej 5 • DK-2100 • Copenhagen • Denmark Phone +45 22874004 • Fax +45 35 32 04 60 www. atomistix. com Atomistix has attracted a strong team of leading experts in nanotechnology modeling and technology marketing The team
Atomistix is pursuing a global strategy Establishing subsidiaries in Asia and North America Copenhagen Montreal www. atomistix. com Singapore
Atomistix is establishing distribution channels around the world China: Hong Cam Japan: Cybernet Systems Taiwan: Pitotech Montreal World Scientific Publishing Worldwide promotion & marketing
Atomistix’s products www. atomistix. com
Conventional Density Functional Theory (DFT) solves two kinds of problems: Periodic systems Finite isolated system Gaussian-98 VASP CASTEP(accelerys) DMOL(accelrys) Device model: Molecular device is neither finite nor periodic Atomistix Tool Kit (Tran. SIESTA-C)
toolkit SIESTA FORTRAN code Developed by 3 scientific groups in Spain. 1994 Development history Tran. SIESTA FORTRAN code Developed at the Technical University of Denmark. Mc. DCAL C code Developed at Mc. Gill University Montreal. 2000 Atomistix Tool Kit and Tran. SIESTA-C C++ code in development at the Niels Bohr Institute, the Technical University of Denmark, and Mc. Gill University 2004
Reputation of Mc. Dcal-Transiesta: • 16 invited talks at international conferences in 2003. Over 30 invited talks at conferences since 2001. • Highlights: Invited talk at the March Meeting of American Physical Society, 2002; 2004; invited talk at American Chemical Society 2003; Keynote speaker at Trends in Nanotechnology 2003. • Over 30 papers published in high impact journals by the collaboration since 2001. • About 100 research groups use the packages and the list is growing. • Students hired by: Harvard, Cornell, HP-Labs, NASA, and several other US institutions. • Strong interests by industry.
Atomistix Virtual Nano. Lab User-friendly modeling of nanotechnology Crystal Molecule Nanoscope Energy Spectrometer Two-probe Crystal Grower & Manipulator Atomistix Tool Kit (ATK) State-of-the-art quantum-mechanical models Density functional theory, non-equilibrium Green’s function, pseudopotentials, numerical basis sets, semi-empirical models, etc.
Atomistix Virtual Nano. Lab Market segments Current market Potential market 1. Electronics Molecular electronics X Carbon nanotubes X Semiconductor devices (X) Spintronics X Plastic electronics X 2. Equipment STM and other equipment X 3. Life sciences Bio molecules X Bio systems X 4. Chemistry Surface properties X Molecular thermodynamics X 5. Material science General material modelling X 6. Education Student’s edition X
New developments VNL Components (ease of use, functionality) Molecular electronics builder Nanotube builder Interface builder One-probe surface science Module (STM, LEED, AFM, . . . ) Solid state experimental module (NMR, XPS, . . . ) ATK Components (efficiency, accuracy, functionality) Spin DFT functionals (GGA, Full exchange, . . . ) Parallel version Semi empirical methods (Extended huckel, AM 1, O(N) methods PAW PW, Gaussian orbitals Transient transport k·p
New module for Large scale quantum simulations Goal: 1. 000 atoms on a supercomputer MD simulation of 5000 atoms on one CPU, to be released 2005/2006
Further Info: visit our booth • See DEMO of Virtual Nano. Lab • Get the Carbon Nano. Tube periodic Table • Get 2 months free trial version of Virtual Nano. Lab www. atomistix. com
Applications www. atomistix. com
Transport in nanotubes Tube Defect Tube Stone-Wales defect in (10, 10)-nanotube (440 atoms) Meta stable Ground State Mozos, PRB 65, 165401
Metal-tube contacts MCDCAL: J. Taylor, H. Guo, J. Wang, PRB 63, 245407 (2001). J. Taylor, Ph. D thesis (2000);
Tube-tube capacitance (12, 12)-(5, 5) nanotube junction (12, 0)/(6, 6) junction Zero conductance due to angular momentum mismatch Hong Guo et. Al.
Si-Si. O 2 -Si interface Silicon - a-Cristobalite - Silicon
Transmission Si-Si. O 2 -Si interface
Summary • NEGF-DFT implementation ATK allows one to analyze charge transport from atomistic first principles without any phenomenological parameters. • Direct quantitative comparisons can now be made to measured data, on molecules with very large resistances. • ATK is based on a modern code design which allows easy extension to handle many future atomic-scale modeling tasks. • Atomistix Virtual Nano. Lab provides an intuitive user interface to nanoscale simulations with ATK.