Transferable Tight Binding Model for Strained Heterostructures
22 Oct 2016 | Online Presentations | Contributor(s): Yaohua Tan, Michael Povolotskyi, Tillmann Christoph Kubis, Timothy Boykin, Gerhard Klimeck
IWCE 2015 presentation.
Tight Binding Parameters by DFT mapping
12 Sep 2012 | Presentation Materials | Contributor(s): Yaohua Tan, Michael Povolotskyi, Tillmann Christoph Kubis, Yu He, Zhengping Jiang, Timothy Boykin, Gerhard Klimeck
The Empirical Tight Binding(ETB) method is widely used in atomistic device simulations. The reliability of such simulations depends very strongly on the choice of basis sets and the ETB parameters. The traditional way of obtaining the ETB parameters is by fitting to experiment data,or critical...
Self-energies: Opening Doors for Nanotechnology
07 Apr 2016 | Online Presentations | Contributor(s): Tillmann Christoph Kubis
In this talk, it will be shown how the concept of self-energies can be used to interface all these fields into the same nanotechnology modeling framework. Self-energies are most commonly used in the quantum transport method of nonequilibrium Green’s functions (NEGF). The NEGF method is...
Resonant Tunneling Diode Simulation with NEGF
18 Aug 2008 | Tools | Contributor(s): Hong-Hyun Park, Zhengping Jiang, Arun Goud Akkala, Sebastian Steiger, Michael Povolotskyi, Tillmann Christoph Kubis, Jean Michel D Sellier, Yaohua Tan, SungGeun Kim, Mathieu Luisier, Samarth Agarwal, Michael McLennan, Gerhard Klimeck, Junzhe Geng
Simulate 1D RTDs using NEGF.
Quantum transport in semiconductor nanostructures
03 Mar 2010 | Papers | Contributor(s): Tillmann Christoph Kubis
PhD thesis of Tillmann Christoph KubisThe main objective of this thesis is to theoretically predict the stationary charge and spin transport in mesoscopic semiconductor quantum devices in the presence of phonons and device imperfections. It is well known that the nonequilibrium Green's function...
Quantum Dot Lab
12 Nov 2005 | Tools | Contributor(s): Prasad Sarangapani, James Fonseca, Daniel F Mejia, James Charles, Woody Gilbertson, Tarek Ahmed Ameen, Hesameddin Ilatikhameneh, Andrew Roché, Lars Bjaalie, Sebastian Steiger, David Ebert, Matteo Mannino, Hong-Hyun Park, Tillmann Christoph Kubis, Michael Povolotskyi, Michael McLennan, Gerhard Klimeck
Compute the eigenstates of a particle in a box of various shapes including domes, pyramids and multilayer structures.
Nonequilibrium Green’s functions theory: Transport and optical gain in THz quantum cascade lasers
24 Mar 2010 | Online Presentations | Contributor(s): Tillmann Christoph Kubis
Quantum cascade lasers (QCLs) are promising sources of coherent THz radiation. However, state of the art THz-QCLs are still limited to cryogenic temperatures. The charge transport in these QCLs is subject to coherent quantum phenomena, such as quantum tunneling, confinement and interferences as...
Nonequilibrium Green's Functions: Reliably Predicting Chemical Reactions
07 Mar 2017 | Online Presentations | Contributor(s): Tillmann Christoph Kubis
In this talk, an introductory overview of the nonequilibrium Green’s function (NEGF) method will be given. NEGF results in state-of the art semiconductor nanodevices will illustrate the strengths of the method. Unique benefits of the method for molecular chemistry will be highlighted...
NEMO5: Why must we treat topological insulator nanowires atomically?
13 Oct 2015 | Online Presentations | Contributor(s): Fan Chen, Michael J. Manfra, Gerhard Klimeck, Tillmann Christoph Kubis
IWCE 2015 presentation. Abstract and more information to be added at a later date.
NEMO5 Tutorials (2012 Summer School)
19 Jul 2012 | Courses | Contributor(s): James Fonseca, Tillmann Christoph Kubis, Michael Povolotskyi, Jean Michel D Sellier, Parijat Sengupta, Junzhe Geng, Mehdi Salmani Jelodar, Seung Hyun Park, Gerhard Klimeck
While the general topics presented in the summer school materials are still applicable, many details have changed. If you are looking at these to learn how to use NEMO5, check out the newer materials here: https://nanohub.org/resources/21824
NEMO5 Tutorial 6A: Device Simulation - Transport (Double Gate)
18 Jul 2012 | Online Presentations | Contributor(s): Mehdi Salmani Jelodar, Seung Hyun Park, Zhengping Jiang, Tillmann Christoph Kubis, Michael Povolotskyi, Gerhard Klimeck
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NEMO5 Overview Presentation
17 Jul 2012 | Online Presentations | Contributor(s): Tillmann Christoph Kubis, Michael Povolotskyi, Jean Michel D Sellier, James Fonseca, Gerhard Klimeck
This presentation gives an overview of the current functionality of NEMO5.
NEMO5 Latest Version Source
22 Feb 2012 | Downloads | Contributor(s): James Fonseca, Michael Povolotskyi, Tillmann Christoph Kubis, Jean Michel D Sellier
Revision 24185 uploaded on December 16th, 2016.Revision 23455 updated on August 8th, 2016 Revision 21229 updated on Sept 2, 2015. Use this if you want to build NEMO5 from source.
NEMO5 and 2D Materials: Tuning Bandstructures, Wave Functions and Electrostatic Screening
18 Oct 2016 | Online Presentations | Contributor(s): Tillmann Christoph Kubis
In this talk, I will briefly discuss the MLWF approach and compare it to DFT and atomistic tight binding. Initial results using the MLWF approach for 2D material based devices will be discussed and compared to experiments. These results unveil systematic band structure changes as functions of the...
Mode Space Tight Binding Model for Ultra-Fast Simulations of III-V Nanowire MOSFETs and Heterojunction TFETs
12 Nov 2015 | Online Presentations | Contributor(s): Aryan Afzalian, Jun Huang, Hesameddin Ilatikhameneh, Santiago Alonso Perez Rubiano, Tillmann Christoph Kubis, Michael Povolotskyi, Gerhard Klimeck
IWCE 2015 presentation. we explore here the suitability of a mode space tight binding algorithm to various iii-v homo- and heterojunction nanowire devices. we show that in iii-v materials, the number of unphysical modes to eliminate is very high compared to the si case previously reported...
IWCN 2021: Recursive Open Boundary and Interfaces Method for Material Property Predictions
13 Jul 2021 | Online Presentations | Contributor(s): James Charles, Sabre Kais, Tillmann Christoph Kubis
In this presentation, we show that assuming periodicity elevates a small perturbation of a periodic cell into a strong impact on the material property prediction. Periodic boundary conditions can be applied on truly periodic systems only. More general systems should apply an open boundary...
IWCN 2021: How to Preserve the Kramers-Kronig Relation in Inelastic Atomistic Quantum Transport Calculations
15 Jul 2021 | Online Presentations | Contributor(s): Daniel Alberto Lemus, James Charles, Tillmann Christoph Kubis
The nonequilibrium Green’s function method (NEGF) is often used to predict quantum transport in atomically resolved nanodevices. This yields a high numerical load when inelastic scattering is included. Atomistic NEGF had been regularly applied on nanodevices, such as nanotransistors....
IWCN 2021: Density Functional Theory Modeling of Chemical Reactions at Interfaces
13 Jul 2021 | Online Presentations | Contributor(s): Namita Narendra, Jessica Wang, James Charles, Tillmann Christoph Kubis
In this work, we introduce a DFT-based method to predict energies of solute molecules in bulk solution and in various distances to solvent/air interfaces. The solute and all solvent molecules (~1400 atoms) are explicitly considered, and their electrons solved self-consistently in density...
Graphene Layer Structure with 3% Random Silicon
02 Aug 2019 | Downloads | Contributor(s): James Charles, Sabre Kais, Tillmann Christoph Kubis
This .xyz file contains a 11,520,000 atoms structure of graphene with randomly placed Silicon. The concentration of Silicon is approximately 3%. This structure file was used to create the data in the paper "Recursive open boundary and interfaces method for material modeling, exemplified on...
Empirical Tight-binding Parameterization of SmSe in the sp3d5f7s* model
26 Mar 2013 | Downloads | Contributor(s): Zhengping Jiang, Marcelo Kuroda, Yaohua Tan, Dennis M. Newns, Michael Povolotskyi, Timothy Boykin, Tillmann Christoph Kubis, Gerhard Klimeck, Glenn J. Martyna
The Empirical Tight Binding(ETB) method is widely used in atomistic device simulations. The reliability of such simulations depends very strongly on the choice of basis sets and the ETB parameters.The Piezoelectronic Transistor (PET) has been proposed as a post-CMOS device for fast, low-power...
Brillouin Zone Viewer
25 Jan 2011 | Tools | Contributor(s): Prasad Sarangapani, Arun Goud Akkala, Sebastian Steiger, Hong-Hyun Park, Yosef Borga, Tillmann Christoph Kubis, Michael Povolotskyi, Gerhard Klimeck
Visualize Brillouin zones of different crystals and different unit cells
Band Structure Lab
19 May 2006 | Tools | Contributor(s): Samik Mukherjee, Kai Miao, Abhijeet Paul, Neophytos Neophytou, Raseong Kim, Junzhe Geng, Michael Povolotskyi, Tillmann Christoph Kubis, Arvind Ajoy, Bozidar Novakovic, James Fonseca, Hesameddin Ilatikhameneh, Sebastian Steiger, Michael McLennan, Mark Lundstrom, Gerhard Klimeck
Computes the electronic and phonon structure of various materials in the spatial configuration of bulk , quantum wells, and wires
Atomistic Green’s Functions: The Beauty of Self-energies
16 Sep 2020 | Online Presentations | Contributor(s): Tillmann Christoph Kubis
This presentation gives an introduction to NEGF. It will be explained how self-energies cause NEGF to fundamentally differ from most other quantum methods. Atomistic examples of phonon and impurity scattering self-energies agree quantitatively with experiments.
1D Heterostructure Tool
04 Aug 2008 | Tools | Contributor(s): Arun Goud Akkala, Sebastian Steiger, Jean Michel D Sellier, Sunhee Lee, Michael Povolotskyi, Tillmann Christoph Kubis, Hong-Hyun Park, Samarth Agarwal, Gerhard Klimeck, James Fonseca, Archana Tankasala, Kuang-Chung Wang, Chin-Yi Chen, Fan Chen
Poisson-Schrödinger Solver for 1D Heterostructures