The keldyshschwinger contour is a convenient bookkeeping device which allows you to derive simple expressions within nonequilibrium green function theory in compact form. For modeling the transport of carriers in nanoscale devices, a green function formalism is the most accurate approach. Density functional nonequilibrium greens function dft. Application of a nonequilibrium greens function method.
This is shown in great detail by using negf as a starting point and developing in 3 directions to obtain the usual transportrelated expressions. It is clear that quantitative simulation tools for this new. The rise in popularity was driven first by the experimental investigations of mesoscopic physics made possible by high quality semiconductor heterostructures grown by. In this study we perform the analysis of multiband quantum transport in nanoscale devices based on a nonequilibrium greens function negf formalism coupled selfconsistently with the poisson equation. The nonequilibrium greens function method for semiconductor light emitting diode simulation zhelio andreev1, akshay shedbalkar1, and bernd witzigmann1 1 university of kassel, dept. This will the basis for the following discussion of nonequilibrium green functions. Distributed nonequilibrium greens function algorithms for the simulation of nanoelectronic devices with scattering stephen cauley, mathieu luisier, venkataramanan balakrishnan, gerhard klimeck, and. Pdf nonequilibrium greens function method for modeling. Received 24 july 2000 the nonequilibrium greens function negf formalism provides a sound conceptual basis for the devlopment of atomiclevel quantum mechanical simulators that will be needed. However, our simulation on nanoscale device shows excess noise at high current levels, but not socalled full shot noise because of much phasebreaking. Pdf ballistic calculation of nonequilibrium greens. Acoustic phonon scattering is included, causing transport to deviate from ballistic in a realistic.
Due to the complexity of the formalism, one should have a deep understanding of the underlying principles and use smart approximations and numerical methods for solving the kinetic. In this paper, we present a new method to calculate the steadystate noise at zero fre. Materials research society symposium proceedings, vol. Basics of nonequilibrium electrodynamics on the nano scale c. The method is implemented into our recently developed computer package opedevs to investigate transport properties of electrons in nanoscale devices and lowdimensional materials. The steady state equation for the greens function is defined as 3. The nonequilibrium greens function method for nanoscale device simulation computational microelectronics pourfath, mahdi on. Simulations of semiconductor laser using nonequilibrium. Efficient solution algorithm of nonequilibrium greens. The simulation is based on a nonequilibrium greens function negf method. A brief introduction to nonequilibrium green functions the keldyshschwinger timecontour. The dyson equation central equation of this method is derived and written in a basis suitable for numerical implementation.
Mathematical details in the application of nonequilibrium. The simulation uses the nonequilibrium greens function negf approach to calculate the. Green function techniques in the treatment of quantum transport at the molecular scale d. Nonequilibrium greens function negf simulation of metallic carbon nanotubes including vacancy defects. Landauerlike theory, kinetic theory and greenkubo linear response theory. A novel method of simulating edgeemitting semiconductor lasers in a nonequilibrium steadystate is developed. Nonequilibrium green functions i joachim keller literature. Jauho, quantum kinetics in transport and optics of semiconductors j. We report a density functional nonequilibrium greens function dftnegf study of electrical transport and switching behavior in a single molecular conductor consisting of a 1,4benzenedithiolate bdt molecular wire with one sulfur end group bonded to an au1 1 1 substrate and the other to a monatomic auscanning tunneling microscope stm tip. Benchmark density functional theory calculations for nanoscale conductance m. We present an overview of electronic device modeling using nonequilibrium green function techniques.
The nonequilibrium greens function method for nanoscale device simulation computational microelectronics. Open boundary conditions and oxide tunneling are treated on an equal footing. Device divided into classical driftdiffusion dd regime mainly in vicinity of contacts and quantum ballistic transport qbt regime. In this thesis we showed that nonequilibrium greens function perturbation theory negf is really the overarching perturbative transport theory. We will introduce a timeordered green function on the special contour ci. The negf method has been implemented into many computer packages with different sophisticated. Received 24 july 2000 the nonequilibrium greens function negf formalism provides a sound conceptual ba. Nonequilibrium greens functions negf and their application to quantum conductance in nanojunctions the lectures are meant for postgraduate and good 4th year undergraduate students, although they could also be useful to anybody wishing to familiarise herhimself with negf and their.
Application of a nonequilibrium greens function method to electrical transport through single molecularassembled metallic nanoparticles. Same global poissons equation solver used in both dd and qbt regimes. Homeengineering technologyelectronics the nonequilibrium greens function method for nanoscale device simulation. Thus it motivates the use of more realistic full band structures in quantum transport simulations. The nonequilibrium greens function negf formalism provides a sound conceptual basis for the devlopment of atomiclevel quantum mechanical simulators that. Benchmark density functional theory calculations for.
Computational microelectronics editor siegfried selberherr technical university vienna. The nonequilibrium green s function method for nanoscale device simulation. Due to the complexity of the formalism, one should have a deep understanding of the underlying principles and use smart approximations and numerical methods for solving the kinetic equations at a reasonable computational time. Everyday low prices and free delivery on eligible orders. Distributed nonequilibrium greens function algorithms. Abstract the nonequilibrium greens function negf formalism provides a sound conceptual basis for the devlopment of atomiclevel quantum mechanical simulators that will be needed for nanoscale devices of the future. A ballistic calculation of a full quantum mechanical system is presented to study 2d nanoscale devices. Green function techniques in the treatment of quantum. Introduction to the one particle negf equations, condmat0210519 2002. Seamless integration of qbt and dd in the apsys software.
For modeling the transport of carriers in nanoscale devices, a greenfunction formalism is the most accurate approach. Read the nonequilibrium greens function method for nanoscale device simulation by mahdi pourfath available from rakuten kobo. This is the most accurate full quantum model yet applied to 2d device simulation. Buy the nonequilibrium greens function method for nanoscale device simulation computational microelectronics 2014 by mahdi pourfath isbn. Pourfath the nonequilibrium greens function method. Basics of nonequilibrium electrodynamics on the nanoscale. Efficient solution algorithm of nonequilibrium greens functions in atomistic tight binding representation.
The nonequilibrium green s function method for nanoscale device simulation mahdi pourfath auth. The nonequilibrium greens function method for nanoscale device simulation free chm, pdf ebooks download. The dyson equation central equation of this method is derived and written in. Cuniberti 1 institute for theoretical physics, university of regensburg, d93040 regensburg, germany. Nonequilibrium greens function crosslight software. Nonequilibrium greens function method for modeling quantum electron transport in nano scale devices with anisotropic multiband structure.
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