English
Related papers

Related papers: A knitting algorithm for calculating Green functio…

200 papers

We study the transport of energy in a finite linear harmonic chain by solving the Heisenberg equation of motion, as well as by using nonequilibrium Green's functions to verify our results. The initial state of the system consists of two…

Statistical Mechanics · Physics 2012-10-02 Eduardo C. Cuansing , Huanan Li , Jian-Sheng Wang

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

Strongly correlated electron systems are challenging to calculate, and entanglement in such systems is not widely analyzed. We present an approach that can be used as a post-processing step for calculating the two-site reduced density…

Strongly Correlated Electrons · Physics 2024-05-29 Gergő Roósz , Anna Kauch , Frederic Bippus , Daniel Wieser , Karsten Held

We develop a finite-element technique that allows one to evaluate correction of the order of $G_Q$ to various transport characteristics of arbitrary nanostructures. Common examples of such corrections are weak localization effect on…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 G. Campagnano , Yu. V. Nazarov

First theoretical and numerical results on the global structure of the energy shell, the Green function spectra and the eigenfunctions, both localized and ergodic, in a generic conservative quantum system are presented. In case of quantum…

Condensed Matter · Physics 2009-10-28 G. Casati , B. V. Chirikov , I. Guarneri , F. M. Izrailev

We describe microscopic theory for the quantum transport through finite interacting systems connected to noninteracting leads. It can be applied to small systems such as quantum dots, quantum wires, atomic chain, molecule, and so forth. The…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Akira Oguri

In this paper, we propose a new Green's function embedding method called PEXSI-$\Sigma$ for describing complex systems within the Kohn-Sham density functional theory (KSDFT) framework, after revisiting the physics literature of Green's…

Computational Physics · Physics 2016-10-20 Xiantao Li , Lin Lin , Jianfeng Lu

We have modeled transport properties of nanostructures using the Green's function method within the framework of the density-functional theory. The scheme is computationally demanding so that numerical methods have to be chosen carefully. A…

Computational Physics · Physics 2007-05-23 Paula Havu , Ville Havu , Martti J. Puska , Mikko H. Hakala , Adam S. Foster , Risto M. Nieminen

We propose an improved quantum algorithm to calculate the Green's function through real-time propagation, and use it to compute the retarded Green's function for the 2-, 3- and 4-site Hubbard models. This novel protocol significantly…

Quantum Physics · Physics 2022-10-21 Francesco Libbi , Jacopo Rizzo , Francesco Tacchino , Nicola Marzari , Ivano Tavernelli

Quantum many-body methods provide a systematic route to computing electronic properties of molecules and materials, but high computational costs restrict their use in large-scale applications. Due to the complexity in many-electron…

We apply a computationally efficient approach to study the time- and energy-resolved spectral properties of a two-site Hubbard model using the nonequilibrium Green's function formalism. By employing the iterative generalized Kadanoff-Baym…

Strongly Correlated Electrons · Physics 2025-06-04 Yaroslav Pavlyukh , Riku Tuovinen

The Wave Function Matching (WFM) technique has recently been developed for the calculation of electronic transport in quantum two-probe systems. In terms of efficiency it is comparable with the widely used Green's function approach. The WFM…

An analytical Green's function is developed to study the acoustic scattering by a flat plate with a serrated edge. The scattered pressure is solved using the Wiener-Hopf technique in conjunction with the adjoint technique. It is shown that…

Fluid Dynamics · Physics 2023-05-10 Benshuai Lyu

We investigate the influence of a time dependent, homogeneous electric field on scattering properties of non-interacting electrons in an arbitrary static potential. We develop a method to calculate the (Keldysh) Green's function in two…

Disordered Systems and Neural Networks · Physics 2009-10-30 Tobias Brandes

Electron transport properties in nanostructures can be modeled, for example, by using the semiclassical Wigner formalism or the quantum mechanical Green's functions formalism. We compare the performance and the results of these methods in…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Paula Havu , Noora Tuomisto , Riikka Vaananen , Martti J. Puska , Risto M. Nieminen

In this work, we propose an efficient computational scheme for first-principle quantum transport simulations to evaluate the open-boundary conditions. Its partitioning differentiates from conventional methods in that the contact self-energy…

Materials Science · Physics 2021-01-01 Guido Gandus , Youseung Lee , Daniele Passerone , Mathieu Luisier

We formulate the dynamical mean field theory directly in the continuum. For a given definition of the local Green's function, we show the existence of a unique functional, whose stationary point gives the physical local Green's function of…

Strongly Correlated Electrons · Physics 2009-02-05 R. Chitra , G. Kotliar

A quantum algorithm is developed to calculate decay rates and cross sections using quantum resources that scale polynomially in the system size assuming similar scaling for state preparation and time evolution. This is done by computing…

High Energy Physics - Theory · Physics 2020-11-18 Anthony Ciavarella

We use multiband real space Green's functions computed using open-boundary conditions for clean GaN to exactly solve the potential-scattering Dyson equation to obtain the electronic structure of single nitrogen and gallium vacancies. From…

Materials Science · Physics 2026-05-26 Joseph Sink , Michael E. Flatté

I present a new approach to the many-body ground state of quantum-Hall systems. The method describes the behavior of a two-dimensional electron system at all Landau-level filling factors $\nu$, continuously as a function of magnetic field,…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 S. A. Mikhailov