Brillouin Zone Viewer Tool

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Network for Computational Nanotechnology (NCN) Purdue, Norfolk State, Northwestern, MIT, Molecular Foundry, UC Berkeley, Univ. of Illinois, UTEP Brillouin Zone Viewer Tool Arun Goud Sebastian Steiger Michael Povolotskyi Tillmann Kubis Hong-Hyun Park Gerhard Klimeck Electrical and Computer Engineering Purdue University, West Lafayette IN, USA Brillouin Zone Tool Purpose of the tool Users can visualize 1st Brillouin zones of the following common crystal lattice systems: - Cubic systems (Simple, BCC & FCC) - Hexagonal (Wurtzite) - Rhombohedral (Bi2TeO3) - Graphene (Honeycomb) Tab1 -> Choose lattice type Tab2 -> Define lattice vector coordinates & number of translations along each coordinate needed to create the unit cell Theory Crystal lattice Bravais lattice atomic basis Real-space lattice: As Ga 2 atoms zincblende fcc A,B,C = Bravais lattice vectors Reciprocal lattice: Atomic basis has no influence on rec. lattice 1st Brillouin zone = set of points in reciprocal space which are closer to 0 than to any other reciprocal lattice vector Features Both primitive & conventional (cubic) lattice translation vectors can be specified for the cubic systems Only primitive translation vectors are currently supported for - Graphene - Hexagonal - Rhombohedral Output of the tool: • Brillouin zone • VTK file • Real space structure & unit cell • Input deck for NEMO5 • Output log Inputs - Lattice Vectors & Translations FCC example: Cubic indices Primitive indices . Translation determines multiples of the A, B & C vectors . Shape of unit cell & hence the Brillouin zone will be altered by changing the translation field entry . Input lattice parameters (depends on lattice type) History of the Tool The Brillouin Zone viewer tool is currently in its 1.0 version. Rappture GUI for the tool by Arun Goud. NEMO5 simulation engine by Sebastian Steiger, Michael Povolotskyi, Tillmann Kubis and Hong-Hyun Park. General supervision: Dr. Gerhard Klimeck. Last update of this document: April 2011.

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