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Nanoelectronic Modeling Lecture 33: Alloy Disorder in Bulk
04 Aug 2010 | | Contributor(s):: Gerhard Klimeck, Timothy Boykin, Chris Bowen
This presentation discusses disorder in AlGaAs unstrained systems in bulk. Bandstructure of an ideal simple unit cellWhat happens when there is disorder?Concept of a supercellBand folding in a supercellBand extraction from the concept of approximate bandstructureComparison of alloy disorder with...
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Thermoelectric Nanotechnology
27 Jul 2010 | | Contributor(s):: Mark Lundstrom
his talk is an undergraduate level introduction to the field. After a brief discussion of applications, the physics of the Peltier effect is described, and the Figure of Merit (FOM), ZT, which controls the efficiency of a thermoelectric refrigerator or electric power generator, is discussed. The...
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ABACUS Exercise: Bandstructure – Kronig-Penney Model and Tight-Binding Exercise
20 Jul 2010 | | Contributor(s):: Dragica Vasileska, Gerhard Klimeck
The objective of this exercise is to start with the simple Kronig-Penney model and understand formations of bands and gaps in the dispersion relation that describes the motion of carriers in 1D periodic potentials. The second exercise examines the behavior of the bands at the Brillouin zone...
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DFT calculations with Quantum ESPRESSO
07 Jul 2010 | | Contributor(s):: Janam Jhaveri, Ravi Pramod Kumar Vedula, Alejandro Strachan, Benjamin P Haley
DFT calculations of molecules and solids
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Nanoelectronic Modeling Lecture 25a: NEMO1D - Full Bandstructure Effects
02 Mar 2010 | | Contributor(s):: Gerhard Klimeck
(quantitative RTD modeling at room temperature)
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Band Structure Lab Exercise
28 Jun 2010 | | Contributor(s):: Gerhard Klimeck, Parijat Sengupta, Dragica Vasileska
Investigations of the electron energy spectra of solids form one of the most active fields of research. Knowledge of band theory is essential for application to specific problems such as Gunn diodes, tunnel diodes, photo-detectors etc. There are several standard methods to compute the band...
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Ripples and Warping of Graphene: A Theoretical Study
19 May 2010 | | Contributor(s):: Umesh V. Waghmare
We use first-principles density functional theory based analysis to understand formation of ripples in graphene and related 2-D materials. For an infinite graphene, we show that ripples are linked with a low energy branch of phonons that exhibits quadratic dispersion at long wave-lengths. Many...
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Tight-Binding Band Structure Calculation Method
02 Jun 2010 | | Contributor(s):: Dragica Vasileska, Gerhard Klimeck
This set of slides describes on simple example of a 1D lattice, the basic idea behind the Tight-Binding Method for band structure calculation.
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InAs: Evolution of iso-energy surfaces for heavy, light, and split-off holes due to uniaxial strain.
21 May 2010 | | Contributor(s):: Abhijeet Paul, Denis Areshkin, Gerhard Klimeck
Movie was generated using Band Structure Lab tool at nanoHUB and allows to scan over four parameters:Hole energy measured from the top of the corresponding band (i.e. the origin of energy scales for LH and SOH is different)Strain direction: [001], [110], [111]Carrier type: LH, HH, SOHStrain...
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Band Structure Calculation: General Considerations
17 May 2010 | | Contributor(s):: Dragica Vasileska
This set of slides explains to the users the concept of valence vs. core electrons, the implications of the adiabatic approximation on the separation of the total Hamiltonian of the system and the mean-field approximation used in ab initio bandstructure approaches. It then gives systematic...
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Empirical Pseudopotential Method: Theory and Implementation
16 May 2010 | | Contributor(s):: Dragica Vasileska
This tutorial first teaches the users the basic theory behind the Empirical Pseudopotential (EPM)Bandstructure Calculation method. Next, the implementation details of the method are described and finally a MATLAB implementation of the EPM is provided.vasileska.faculty.asu.eduNSF
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ninithi
07 May 2010 | | Contributor(s):: Chanaka Suranjith Rupasinghe, Mufthas Rasikim
ninithi which is a free and opensource modelling software, can be used to visualize and analyze carbon allotropes used in nanotechnology. You can generate 3-D visualization of Carbon nanotubes, Fullerenes, Graphene and Carbon nanoribbons and analyze the band structures of nanotubes and graphene.
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Nanotechnology Animation Gallery
20 Apr 2010 | | Contributor(s):: Saumitra Raj Mehrotra, Gerhard Klimeck
Animations and visualization are generated with various nanoHUB.org tools to enable insight into nanotechnology and nanoscience. Click on image for detailed description and larger image download. Additional animations are also...
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Electronic band structure
09 Apr 2010 | | Contributor(s):: Saumitra Raj Mehrotra, Gerhard Klimeck
In solid-state physics, the electronic band structure (or simply band structure) of a solid describes ranges of energy in which an electron is "forbidden" or "allowed". The band structure is also often called the dispersion or the E(k) relationship. It is a mathematical...
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Nanoelectronic Modeling Lecture 25b: NEMO1D - Hole Bandstructure in Quantum Wells and Hole Transport in RTDs
02 Mar 2010 | | Contributor(s):: Gerhard Klimeck
Heterostructures such as resonant tunneling diodes, quantum well photodetectors and lasers, and cascade lasers break the symmetry of the crystalline lattice. Such break in lattice symmetry causes a strong interaction of heavy-, light- and split-off hole bands. The bandstructure of holes and the...
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Nanoelectronic Modeling Lecture 26: NEMO1D -
02 Mar 2010 | | Contributor(s):: Gerhard Klimeck
NEMO1D demonstrated the first industrial strength implementation of NEGF into a simulator that quantitatively simulated resonant tunneling diodes. The development of efficient algorithms that simulate scattering from polar optical phonons, acoustic phonons, alloy disorder, and interface roughness...
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Bulk Bandstructure in MATLAB: Pseudopotential Method
08 Feb 2010 | | Contributor(s):: Muhanad Zaki
This code (MATLAB) readily calculates and plots the bandstructure of Silicon (bulk) using the empirical pseudopotential method.Detailed instructions are in the compressed archive.I hope it would be a useful/interesting educational toolNote: If you are running this code in a non-Windows OS (e.g....
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Tillmann Christoph Kubis
https://nanohub.org/members/41945
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nanoMATERIALS SeqQuest DFT
04 Feb 2008 | | Contributor(s):: Ravi Pramod Kumar Vedula, Greg Bechtol, Benjamin P Haley, Alejandro Strachan
DFT calculations of materials
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Illinois ECE 440: Diffusion and Energy Band Diagram Homework
27 Jan 2010 | | Contributor(s):: Mohamed Mohamed
This homework covers Diffusion of Carriers, Built-in Fields and Metal semiconductor junctions.