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Nano Carbon: From ballistic transistors to atomic drumheads
14 May 2008 | | Contributor(s):: Paul L. McEuen
Carbon takes many forms, from precious diamonds to lowly graphite. Surprisingly, it is the latter that is the most prized by nano physicists. Graphene, a single layer of graphite, can serve as an impenetrable membrane a single atom thick. Rolled up into a nanometer-diameter cylinder--a carbon...
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Matdcal
30 Jan 2008 | | Contributor(s):: Kirk Bevan
Non-equilibrium Green's Function Density Functional Theory Simulator
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Introduction to Coulomb Blockade Lab
31 Mar 2008 | | Contributor(s):: Bhaskaran Muralidharan, Xufeng Wang, Gerhard Klimeck
The tutorial is based on the Coulomb Blockade Lab available online at Coulomb Blockade Lab. Students are introduced to the concepts of level broadening and charging energies in artificial atoms (single quantum dots) and molecules (coupled quantum dots).A tutorial level introduction to the...
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Coulomb Blockade Simulation
05 Jul 2006 | | Contributor(s):: Xufeng Wang, Bhaskaran Muralidharan, Gerhard Klimeck
Simulate Coulomb Blockade through Many-Body Calculations in a single and double quantum dot system
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Nanoelectronic Modeling: Multimillion Atom Simulations, Transport, and HPC Scaling to 23,000 Processors
07 Mar 2008 | | Contributor(s):: Gerhard Klimeck
Future field effect transistors will be on the same length scales as “esoteric” devices such as quantum dots, nanowires, ultra-scaled quantum wells, and resonant tunneling diodes. In those structures the behavior of carriers and their interaction with their environment need to be fundamentally...
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MCW07 A Quantum Open Systems Approach to Molecular-Scale Devices
25 Feb 2008 | | Contributor(s):: Yongqiang Xue
Experimental advances in electrically and optically probing individual molecules have provided new insights into the behavior of single quantum objects and their interaction with the nanoenvironments without requiring ensemble average. Molecular-scale devices are open quantum systems whose...
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MCW07 Physics of Contact Induced Current Asymmetry in Transport Through Molecules
25 Feb 2008 | | Contributor(s):: Bhaskaran Muralidharan, owen miller, Neeti Kapur, Avik Ghosh, Supriyo Datta
We first outline the qualitatively different physics involved in the charging-induced current asymmetries in molecular conductors operating in the strongly coupled (weakly interacting) self-consistent field (SCF) and the weakly coupled (strongly interacting) Coulomb Blockade (CB) regimes. The CB...
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Exploring Physical and Chemical control of molecular conductance: A computational study
31 Jan 2008 | | Contributor(s):: Barry D. Dunietz
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Finite Height Quantum Well: an Exercise for Band Structure
31 Jan 2008 | | Contributor(s):: David K. Ferry
Use the Resonant Tunneling Diodes simulation tool on nanoHUB to explore the effects of finite height quantum wells. Looking at a 2 barrier device, 300 K, no bias, other standard variables, and 3 nm thick barriers and a 7 nm quantum well, determine the energies of the two lowest quasi-bound states.
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Path Integral Monte Carlo
13 Dec 2007 | | Contributor(s):: John Shumway, Matthew Gilbert
Tool Description
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Application of the Keldysh Formalism to Quantum Device Modeling and Analysis
14 Jan 2008 | | Contributor(s):: Roger Lake
The effect of inelastic scattering on quantum electron transport through layered semi-conductor structures is studied numerically using the approach based on the non-equilibrium Green's function formalism of Keldysh, Kadanoff, and Baym. The Markov assumption is not made, and the energy coordinate...
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Electron-Phonon and Electron-Electron Interactions in Quantum Transport
14 Jan 2008 | | Contributor(s):: Gerhard Klimeck
The objective of this work is to shed light on electron transport through sub-micron semi-conductor structures, where electronic state quantization, electron-electron interactions and electron-phonon interactions are important. We concentrate here on the most developed vertical quantum device,...
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Can numerical “experiments” INSPIRE physical experiments?
20 Dec 2007 | | Contributor(s):: Supriyo Datta
This presentation was one of 13 presentations in the one-day forum, "Excellence in Computer Simulation," which brought together a broad set of experts to reflect on the future of computational science and engineering.
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NanoElectronic MOdeling: NEMO
20 Dec 2007 | | Contributor(s):: Gerhard Klimeck
This presentation was one of 13 presentations in the one-day forum, "Excellence in Computer Simulation," which brought together a broad set of experts to reflect on the future of computational science and engineering.Novel nanoelectronic devices such as quantum dots, nanowires, and ultra-scaled...
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Carrier Transport at the Nanoscale
27 Nov 2007 | | Contributor(s):: Mark Lundstrom
Fall 2007Note: A more current teaching of this course with online lectures is available as ECE 656: Electronic Transport in Semiconductors (Fall 2011).This is a course about how charge flows in semiconductors with an emphasis on transport at the nanoscale. After a brief review basic concepts, the...
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Engineering at the nanometer scale: Is it a new material or a new device?
06 Nov 2007 | | Contributor(s):: Gerhard Klimeck
This seminar will overview NEMO 3D simulation capabilities and its deployment on the nanoHUB as well as an overview of the nanoHUB impact on the community.
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MCW07 Modeling Molecule-Assisted Transport in Nanotransistors
06 Nov 2007 | | Contributor(s):: Kamil Walczak
Molecular electronics faces many problems in practical device implementation, due to difficulties with fabrication and gate-ability. In these devices, molecules act as the main conducting channel. One could imagine alternate device structures where molecules act as quantum dots rather than...
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MCW07 Simple Models for Molecular Transport Junctions
13 Sep 2007 | | Contributor(s):: Misha Galperin, Abraham Nitzan, Mark Ratner
We review our recent research on role of interactions in molecular transport junctions. We consider simple models within nonequilibrium Green function approach (NEGF) in steady-state regime.
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MCW07 Electronic Level Alignment at Metal-Molecule Contacts with a GW Approach
05 Sep 2007 | | Contributor(s):: Jeffrey B. Neaton
Most recent theoretical studies of electron transport in single-molecule junctions rely on a Landauer approach, simplified to treat electron-electron interactions at a mean-field level within density functional theory (DFT). While this framework has proven relatively accurate for certain systems,...
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MCW07 Modeling Charging-based Switching in Molecular Transport Junctions
23 Aug 2007 | | Contributor(s):: Sina Yeganeh, Misha Galperin, Mark Ratner
We will discuss several proposed explanations for the switching and negative differential resistance behavior seen in some molecular junctions. It is shown that a proposed polaron model is successful in predicting both hysteresis and NDR behavior, and the model is elaborated with image charge...