
CQT: Concepts of Quantum Transport
30 Nov 2006   Contributor(s):: Supriyo Datta
Note: For an expanded version of these lectures see Datta's 2008 NCN@Purdue Summer School presentations onNanoelectronics and the Meaning of Resistance.How does the resistance of a conductor change as we shrink its length all the way down to a few atoms? This is a question that has intrigued...

MOSCNT: code for carbon nanotube transistor simulation
14 Nov 2006   Contributor(s):: Siyu Koswatta, Jing Guo, Dmitri Nikonov
Ballistic transport in carbon nanotube metaloxidesemiconductor fieldeffect transistors (CNTMOSFETs) is simulated using the Nonequilibrium Green’s function formalism. A cylindrical transistor geometry with wrappedaround gate and doped source/drain regions are assumed. It should be noted...

recursive algorithm for NEGF in Matlab
13 Nov 2006   Contributor(s):: Dmitri Nikonov, Siyu Koswatta
This ziparchive contains two Matlab functions for the recursive solution of the partial matrix inversion and partial 3matrix multiplication used in the nonequilibrium Green’s function (NEGF) method.recuresealg3d.m works for 3diagonal matricesrecuresealgblock3d.m works for 3blockdiagonal...

Multidimensional nanoscale device modeling: the finite element method applied to the nonequilibrium Green's function formalism
31 Oct 2006   Contributor(s):: POLIZZI ERIC, Supriyo Datta
This work deals with the modeling and the numerical simulation of quantum transport in multidimensional open nanoscale devices. The electron transport in the device is described using the NonEquilibrium Green's Functions (NEGF) formalism and the variational form of the problem is solved using...

Non Equilibrium Green's Functions for Dummies: Introduction to the One Particle NEGF equations
30 Oct 2006   Contributor(s):: Magnus Paulsson
Non equilibrium Green's function methods are regularly used to calculate current and charge densities in nanoscale (both molecular and semiconductor) conductors under bias. This method is mainly used for ballistic conduction but may be extended to include inelastic scattering. In this tutorial...

Modeling Quantum Transport in Nanoscale Transistors
30 Oct 2006   Contributor(s):: ramesh venugopal
As critical transistor dimensions scale below the 100 nm (nanoscale) regime, quan tum mechanical effects begin to manifest themselves and affect important device performance metrics. Therefore, simulation tools which can be applied to design nanoscale transistors in the future, require new...

Carbon Nanotube Electronics: Modeling, Physics, and Applications
30 Oct 2006   Contributor(s):: Jing Guo
In recent years, significant progress in understanding the physics of carbon nanotube electronic devices and in identifying potential applications has occurred. In a nanotube, low bias transport can be nearly ballistic across distances of several hundred nanometers. Deposition of highκ gate...

A ThreeDimensional Quantum Simulation of Silicon Nanowire Transistors with the EffectiveMass Approximation
30 Oct 2006   Contributor(s):: , POLIZZI ERIC, Mark Lundstrom
The silicon nanowire transistor (SNWT) is a promising device structure for future integrated circuits, and simulations will be important for understanding its device physics and assessing its ultimate performance limits. In this work, we present a threedimensional quantum mechanical simulation...

Electrical Resistance: an Atomistic View
26 Oct 2006   Contributor(s):: Supriyo Datta
This tutorial article presents a “bottomup” view of electrical resistance starting from something really small, like a molecule, and then discussing the issues that arise as we move to bigger conductors. Remark ably enough, no serious quantum mechanics is needed to understand electrical...

Nanoscale MOSFETs: Physics, Simulation and Design
26 Oct 2006 
This thesis discusses device physics, modeling and design issues of nanoscale transistors at the quantum level. The principle topics addressed in this report are 1) an implementation of appropriate physics and methodology in device modeling, 2) development of a new TCAD (technology computer...

Modeling of Nanoscale Devices
19 Oct 2006   Contributor(s):: M. P. Anantram, Mark Lundstrom, Dmitri Nikonov
We aim to provide engineers with an introductionto the nonequilibriumGreen’s function (NEGF) approach, which is a powerful conceptual tool and a practical analysismethod to treat nanoscale electronic devices with quantum mechanicaland atomistic effects. We first review the basis for the...

A Quantum Mechanical Analysis of Channel Access Geometry and Series Resistance in Nanoscale Transistors
19 Oct 2006   Contributor(s):: Ramesh Venugopal, Sebastien Goasguen, Supriyo Datta, Mark Lundstrom
In this paper, we apply a twodimensional quantum mechanical simulation scheme to study the effect of channel access geometries on device performance. This simulation scheme solves the nonequilibrium Green’s function equations selfconsistently with Poisson’s equation and treats the effect of...

Introduction to the Keldysh Nonequilibrium Green Function Technique
06 Oct 2006 
Keldysh nonequilibrium Green function technique is used very widely to describe transport phenomena in mesoscopic systems.The technique is somewhat subtle, and a rigorous treatment would require much more than we have at our disposal, see, for example, the textbookk by Haug and Jauho [1].The...

nanoMOS 2.0: A Two Dimensional Simulator for Quantum Transport in DoubleGate MOSFETs
06 Oct 2006   Contributor(s):: Zhibin Ren, Ramesh Venugopal, Sebastien Goasguen, Supriyo Datta, Mark Lundstrom
A program to numerically simulate quantum transport in double gate MOSFETs is described. The program uses a Green’s function approach and a simple treatment of scattering based on the idea of socalled Büttiker probes. The double gate device geometry permits an efficient mode space approach that...

Simulating Quantum Transport in Nanoscale Transistors: Real versus ModeSpace Approaches
28 Sep 2006   Contributor(s):: Zhibin Ren, Supriyo Datta, Mark Lundstrom, Ramesh Venugopal, D. Jovanovic
In this paper, we present a computationally efficient, twodimensional quantum mechanical sim ulation scheme for modeling electron transport in thin body, fully depleted, nchannel, silicon oninsulator transistors in the ballistic limit. The proposed simulation scheme, which solves the...

Device Physics and Simulation of Silicon Nanowire Transistors
28 Sep 2006 
As the conventional silicon metaloxidesemiconductor fieldeffect transistor (MOSFET) approaches its scaling limits, many novel device structures are being extensively explored. Among them, the silicon nanowire transistor (SNWT) has attracted broad attention from both the semiconductor industry...

Nanoscale Device Modeling: From MOSFETs to Molecules
20 Sep 2006 
This thesis presents a rigorous yet practical approach to model quantum transport in nanoscale electronic devices.As convetional metal oxide semiconductor devices shrink below the one hundred nanometer regime, quantum mechanical effects are beginning to play an increasingly important role in...

Towards MultiScale Modeling of Carbon Nanotube Transistors
20 Sep 2006   Contributor(s):: Jing Guo, Supriyo Datta, Mark Lundstrom, M. P. Anantram
Multiscale simulation approaches are needed in order to address scientific and technological questions in the rapidly developing field of carbon nanotube electronics. In this paper, we describe an effort underway to develop a comprehensive capability for multiscale simulation of carbon nanotube...

Quantum Transport for Nanostructures
17 Sep 2006   Contributor(s):: Mathieu Luisier
Nonequilibrium Green's function techniques, initiated by Schwinger and Kadanoff and Baym allow ones to study the time evolution of a manyparticle quantum sys tem. Knowing the 1particle Green's functions of a given system, one may evaluate 1particle quantities like carrier density or current....

Understanding Phonon Dynamics via 1D Atomic Chains
04 Apr 2006   Contributor(s):: Timothy S Fisher
Phonons are the principal carriers of thermal energy in semiconductors and insulators, and they serve a vital role in dissipating heat produced by scattered electrons in semiconductor devices. Despite the importance of phonons, rigorous understanding and inclusion of phonon dynamics in...