-
ABACUS Tool Suite and Bandstructure and Band Models (Fall 2023)
22 Aug 2023 | | Contributor(s):: Gerhard Klimeck
In the third session, Dr. Klimeck will give a brief overview of ABACUS and demonstrate several bandstructure tools. With these, students can explore the Standard Periodic Potential aka Kronig-Penney model as well as bandstructure formation by transmission through finite barriers....
-
ABACUS Bandstructure Models (Spring 2022)
05 May 2022 | | Contributor(s):: Gerhard Klimeck
In the third session, Dr. Klimeck will give a brief overview of ABACUS and demonstrate several bandstructure tools. With these, students can explore the Standard Periodic Potential aka Kronig-Penney model as well as bandstructure formation by transmission through finite barriers....
-
ABACUS Bandstructure Models (Winter 2021)
21 Dec 2021 | | Contributor(s):: Gerhard Klimeck
In the third session, Dr. Klimeck will give a brief overview of ABACUS and demonstrate several bandstructure tools. With these, students can explore the Standard Periodic Potential aka Kronig-Penney model as well as bandstructure formation by transmission through finite barriers...
-
Bandgap Manipulation of Armchair Graphene nanoribbon
01 Sep 2020 | | Contributor(s):: Lance Fernandes
Bandgap Manipulation is very important for various applications. Optical Devices need smaller Bandgap where as Diode's need larger Bandgap. Armchair graphene Nanoribbon (AGNR) has a special property where if the numbers of atoms are multiple of three or multiple of three plus one, they are...
-
Genetic Algorithm Based Tight Binding Parameterisation
08 Aug 2018 | | Contributor(s):: Samik Mukherjee
This paper is a short description on how to use MATLAB genetic algorithm toolbox for generating tight binding parameters. A Hamiltonian is constructed and interfaced with MATLAB genetic algorithm for generating parameters that have been put in NEMO5 quantum transport software.
-
Transferable Tight Binding Model for Strained Heterostructures
22 Oct 2016 | | Contributor(s):: Yaohua Tan, Michael Povolotskyi, Tillmann Christoph Kubis, Timothy Boykin, Gerhard Klimeck
IWCE 2015 presentation.
-
Bismide Semiconductors: Revolutionising Telecom Lasers
19 Oct 2015 | | Contributor(s):: Muhammad Usman, Christopher A Broderick, Eoin P O\'reilly
Today’s telecomm lasers are plagued with Auger-related losses, which significantly reduce their efficiency and make device cooling essential. We are proposing a radical change in the laser technology by developing a new class of materials, bismide semiconductors. These novel nanomaterials...
-
Density Functional Tight Binding (DFTB) Modeling in the Context of Ultra-Thin Silicon-on-Insulator MOSFETs
10 Oct 2015 | | Contributor(s):: Stanislav Markov
IWCE 2015 presentation. We investigate the applicability of density functional tight binding (DFTB) theory [1][2], coupled to non-equilibrium Green functions (NEGF), for atomistic simulations of ultra-scaled electron devices, using the DFTB+ code [3][4]. In the context of ultra-thin...
-
Tight Binding Parameters by DFT mapping
12 Sep 2012 | | 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...
-
OMEN Nanowire: solve the challenge
05 Feb 2011 | | Contributor(s):: SungGeun Kim
This document includes a challenging problems for OMEN Nanowire users. It challenges users to establish a nanowire transistor structure such that it satisfy the ITRS 2010 requirements.
-
OMEN Nanowire Homework Problems
24 Jan 2011 | | Contributor(s):: SungGeun Kim
OMEN Nanowire homework problems: anyone who has gone through the first-time user guide of OMEN Nanowire and done the examples in the guide should be able to run simulations in these homework problems and find the answers to them.
-
Thermoelectric effects in semiconductor nanostructures: Role of electron and lattice properties
06 Oct 2010 | | Contributor(s):: Abhijeet Paul, Gerhard Klimeck
This presentation covers some aspects of present development in the field of thermoelectricity and focuses particularly on the silicon nanowires as potential thermoelectric materials. The electronic and phonon dispersions are calculated and used for the calculation of thermoelectric properties in...
-
Nanoelectronic Modeling Lecture 40: Performance Limitations of Graphene Nanoribbon Tunneling FETS due to Line Edge Roughness
05 Aug 2010 | | Contributor(s):: Gerhard Klimeck, Mathieu Luisier
This presentation the effects of line edge roughness on graphene nano ribbon (GNR) transitors..Learning Objectives:GNR TFET Simulation pz Tight-Binding Orbital Model 3D Schrödinger-Poisson Solver Device Simulation Structure Optimization (Doping, Lg, VDD) LER => Localized Band Gap States LER =>...
-
Nanoelectronic Modeling Lecture 32: Strain Layer Design through Quantum Dot TCAD
04 Aug 2010 | | Contributor(s):: Gerhard Klimeck, Muhammad Usman
This presentation demonstrates the utilization of NEMO3D to understand complex experimental data of embedded InAs quantum dots that are selectively overgrown with a strain reducing InGaAs layer. Different alloy concentrations of the strain layer tune the optical emission and absorption wavelength...
-
Nanoelectronic Modeling Lecture 29: Introduction to the NEMO3D Tool
04 Aug 2010 | | Contributor(s):: Gerhard Klimeck
This presentation provides a very high level software overview of NEMO3D. The items discussed are:Modeling Agenda and MotivationTight-Binding Motivation and basic formula expressionsTight binding representation of strainSoftware structureNEMO3D algorithm flow NEMO3D parallelization scheme –...
-
Nanoelectronic Modeling Lecture 28: Introduction to Quantum Dots and Modeling Needs/Requirements
20 Jul 2010 | | Contributor(s):: Gerhard Klimeck
This presentation provides a very high level software overview of NEMO1D.Learning Objectives:This lecture provides a very high level overview of quantum dots. The main issues and questions that are addressed are:Length scale of quantum dotsDefinition of a quantum dotQuantum dot examples and...
-
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...
-
Tight-Binding Band Structure Calculation Method
08 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.
-
Carbon nanotube bandstructure
22 Apr 2010 | | Contributor(s):: Saumitra Raj Mehrotra, Gerhard Klimeck
Carbon nanotubes are allotropes of carbon with a cylindrical nanostructure, and can be categorized into single-walled nanotubes (SWNT) and multi-walled nanotubes (MWNT). These cylindrical carbon molecules have novel properties that make them potentially useful in many nanotechnology applications,...
-
Nanoelectronic Modeling Lecture 25b: NEMO1D - Hole Bandstructure in Quantum Wells and Hole Transport in RTDs
09 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...