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Related papers: Self Consistent NEGF-LLG Model for Spin-Torque Bas…

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Nonequilibrium electronic forces play a central role in voltage-driven phase transitions but are notoriously expensive to evaluate in dynamical simulations. Here we develop a machine learning framework for adiabatic lattice dynamics coupled…

Strongly Correlated Electrons · Physics 2026-01-13 Yunhao Fan , Sheng Zhang , Gia-Wei Chern

We report the investigation of full-counting statistics (FCS) of transferred charge and spin in the transient regime where the connection between central scattering region (quantum dot) and leads are turned on at $t=0$. A general…

Statistical Mechanics · Physics 2014-12-15 Gao-Min Tang , Jian Wang

Based on density functional theory (DFT), we have developed algorithms and a program code to investigate the electron transport characteristics for a variety of nanometer scaled devices in the presence of an external bias voltage. We…

Mesoscale and Nanoscale Physics · Physics 2008-05-14 Woo Youn Kim , Kwang S. Kim

We propose a theoretical model of magnetization switching in a ferromagnetic multilayer by both electric current and microwaves. The electric current gives a spin transfer torque on the magnetization, while the microwaves induce a…

Mesoscale and Nanoscale Physics · Physics 2016-01-22 Tomohiro Taniguchi , Daisuke Saida , Yoshinobu Nakatani , Hitoshi Kubota

We employ Non-equilibrium Green's functions (NEGF) to describe the real-time dynamics of an adsorbate-surface model system exposed to ultrafast laser pulses. For a finite number of electronic orbitals, the system is solved exactly and…

Mesoscale and Nanoscale Physics · Physics 2016-05-04 E. Boström , M. Hopjan , A. Kartsev , C. Verdozzi , C. -O. Almbladh

We use the effective-mass approximation and the density-functional theory with the local-density approximation for modeling two-dimensional nano-structures connected phase-coherently to two infinite leads. Using the non-equilibrium Green's…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Paula Havu , Ville Havu , Martti Puska , Risto Nieminen

We consider a small itinerant ferromagnet exposed to an external magnetic field and strongly driven by a thermally induced spin current. For this model, we derive the quasi-classical equations of motion for the magnetization where the…

Mesoscale and Nanoscale Physics · Physics 2019-01-30 Tim Ludwig , Igor S. Burmistrov , Yuval Gefen , Alexander Shnirman

The standard model of spin-transfer torque (STT) in antiferromagnetic spintronics considers exchange of angular momentum between quantum spins of flowing electrons and noncollinear-to-them localized spins treated as classical vectors. These…

Strongly Correlated Electrons · Physics 2021-05-13 Marko D. Petrovic , Priyanka Mondal , Adrian E. Feiguin , Branislav K. Nikolic

This paper presents an ab initio methodology to account for electron-phonon interactions in 2D materials, focusing on transition metal dichalcogenides (TMDCs). It combines density functional theory and maximally localized Wannier functions…

Mesoscale and Nanoscale Physics · Physics 2023-12-04 Jonathan Backman , Youseung Lee , Mathieu Luisier

We investigate the possibility of exciting self-oscillation in a perpendicular ferromagnet by the spin Hall effect on the basis of a nonlinear analysis of the Landau-Lifshitz-Gilbert (LLG) equation. In the self-oscillation state, the energy…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 Tomohiro Taniguchi

This article presents an overview on recent progress in the theory of nonequilibrium Green functions (NEGF). NEGF, presently, are the only \textit{ab-initio} quantum approach that is able to study the dynamics of correlations for long times…

Strongly Correlated Electrons · Physics 2019-12-20 N. Schluenzen , S. Hermanns , M. Scharnke , M. Bonitz

We overview nonequilibrium Green function combined with density functional theory (NEGF-DFT) modeling of independent electron and phonon transport in nanojunctions with applications focused on a new class of thermoelectric devices where a…

Mesoscale and Nanoscale Physics · Physics 2012-04-19 Branislav K. Nikolic , Kamal K. Saha , Troels Markussen , Kristian S. Thygesen

We introduce diagrammatic technique for Hubbard nonequilibrium Green functions (NEGF). The formulation is an extension of equilibrium considerations for strongly correlated lattice models to description of current carrying molecular…

Mesoscale and Nanoscale Physics · Physics 2016-11-04 Feng Chen , Maicol A. Ochoa , Michael Galperin

The Landau-Lisfhitz-Gilbert (LLG) equation has been the cornerstone of modeling the dynamics of localized spins, viewed as classical vectors of fixed length, within nonequilibrium magnets. When light is employed as the nonequilibrium drive,…

Mesoscale and Nanoscale Physics · Physics 2025-12-11 Felipe Reyes-Osorio , Branislav K. Nikolic

We report the theoretical investigation of noise spectrum of spin current and spin transfer torque for non-colinear spin polarized transport in a spin-valve device which consists of normal scattering region connected by two ferromagnetic…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 Yunjin Yu , Hongxin Zhan , Langhui Wan , Bin Wang , Yadong Wei , Qingfeng Sun , Jian Wang

This article reviews the application of the non-equilibrium Green's function formalism to the simulation of novel photovoltaic devices utilizing quantum confinement effects in low dimensional absorber structures. It covers well-known…

Mesoscale and Nanoscale Physics · Physics 2012-06-14 U. Aeberhard

The transport and gain properties of quantum cascade (QC) structures are investigated using a nonequilibrium Green's function (NGF) theory which includes quantum effects beyond a Boltzmann transport description. In the NGF theory, we…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. -C. Lee , A. Wacker

A dynamical method for inelastic transport simulations in nanostructures is compared with a steady-state method based on non-equilibrium Green's functions. A simplified form of the dynamical method produces, in the steady state in the…

Mesoscale and Nanoscale Physics · Physics 2008-08-19 Eunan J. McEniry , Thomas Frederiksen , Tchavdar N. Todorov , Daniel Dundas , Andrew P. Horsfield

We investigate theoretically nonequilibrium quantum transport in a quantum dot attached to a Majorana bound state. Our approach is based on the Keldysh Green's function formalism, which allows us to investigate the electric current…

Strongly Correlated Electrons · Physics 2014-03-17 S. J. S. da Silva , A. C. Seridonio , J. Del Nero , F. M. Souza

While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green's function formalism combined with density functional theory, in recent years a few time-depedent approaches to…