0000000000306168

AUTHOR

Claudio Verdozzi

showing 3 related works from this author

Merging Features from Green's Functions and Time Dependent Density Functional Theory: A Route to the Description of Correlated Materials out of Equil…

2016

We propose a description of nonequilibrium systems via a simple protocol that combines exchange-correlation potentials from density functional theory with self-energies of many-body perturbation theory. The approach, aimed to avoid double counting of interactions, is tested against exact results in Hubbard-type systems, with respect to interaction strength, perturbation speed and inhomogeneity, and system dimensionality and size. In many regimes, we find significant improvement over adiabatic time dependent density functional theory or second Born nonequilibrium Green's function approximations. We briefly discuss the reasons for the residual discrepancies, and directions for future work.

out of equilibriumexchange-correlation potentialmany body perturbation theoryGeneral Physics and AstronomyPerturbation (astronomy)Non-equilibrium thermodynamicsFOS: Physical sciences02 engineering and technologyResidual01 natural sciencesnon-equilibrium Green's functionCondensed Matter - Strongly Correlated Electronstime dependent density functional theory0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)Statistical physicsnonequilibrium system010306 general physicsAdiabatic processcorrelated materialsPhysicsCondensed Matter - Materials Scienceta114Strongly Correlated Electrons (cond-mat.str-el)Condensed Matter - Mesoscale and Nanoscale PhysicsMaterials Science (cond-mat.mtrl-sci)Time-dependent density functional theory021001 nanoscience & nanotechnologyinteraction strengthperturbation techniquesFunction approximationDensity functional theory0210 nano-technologyCurse of dimensionality
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Disorder and interactions in systems out of equilibrium : the exact independent-particle picture from density functional theory

2017

Density functional theory (DFT) exploits an independent-particle-system construction to replicate the densities and current of an interacting system. This construction is used here to access the exact effective potential and bias of non-equilibrium systems with disorder and interactions. Our results show that interactions smoothen the effective disorder landscape, but do not necessarily increase the current, due to the competition of disorder screening and effective bias. This puts forward DFT as a diagnostic tool to understand disorder screening in a wide class of interacting disordered systems.

Class (set theory)Current (mathematics)Non-equilibrium thermodynamicsFOS: Physical sciences02 engineering and technologyCondensed Matter::Disordered Systems and Neural Networks01 natural sciencesCondensed Matter - Strongly Correlated ElectronsInformationSystems_GENERALdisordered systems0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)strongly correlated systemsDisorder screeningStatistical physics010306 general physicsdensity functional theoryPhysicsta114Condensed Matter - Mesoscale and Nanoscale PhysicsStrongly Correlated Electrons (cond-mat.str-el)tiheysfunktionaaliteoriaDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural Networks021001 nanoscience & nanotechnologynonequilibrium Green's functionParticleDensity functional theory0210 nano-technology
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Effective bias and potentials in steady-state quantum transport: A NEGF reverse-engineering study

2016

Using non-equilibrium Green’s functions combined with many-body perturbation theory, we have calculated steady-state densities and currents through short interacting chains subject to a finite electric bias. By using a steady-state reverse-engineering procedure, the effective potential and bias which reproduce such densities and currents in a non-interacting system have been determined. The role of the effective bias is characterised with the aid of the so-called exchange-correlation bias, recently introduced in a steady-state density-functionaltheory formulation for partitioned systems. We find that the effective bias (or, equivalently, the exchange-correlation bias) depends strongly on th…

PhysicsReverse engineeringHistorySteady state (electronics)Strongly Correlated Electrons (cond-mat.str-el)Condensed Matter - Mesoscale and Nanoscale PhysicsFOS: Physical sciencesInteraction strengthcomputer.software_genreComputer Science ApplicationsEducationCondensed Matter - Strongly Correlated ElectronsQuantum transportPartitioned systemsChain (algebraic topology)Mesoscale and Nanoscale Physics (cond-mat.mes-hall)Green's functionsStatistical physicsPerturbation theorycomplex systemscomputerJournal of Physics: Conference Series
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