Search results for "TDDFT"

showing 8 items of 18 documents

A first-principles time-dependent density functional theory framework for spin and time-resolved angular-resolved photoelectron spectroscopy in perio…

2017

We present a novel theoretical approach to simulate spin, time, and angular-resolved photoelectron spectroscopy (ARPES) from first-principles that is applicable to surfaces, thin films, few layer systems, and low-dimensional nanostructures. The method is based on a general formulation in the framework of time-dependent density functional theory (TDDFT) to describe the real time-evolution of electrons escaping from a surface under the effect of any external (arbitrary) laser field. By extending the so-called t-SURFF method to periodic systems one can calculate the final photoelectron spectrum by collecting the flux of the ionization current trough an analyzing surface. The resulting approach…

PhysicsPhotoemission spectroscopyAngle-resolved photoemission spectroscopyNanotechnology02 engineering and technologyElectronTime-dependent density functional theory021001 nanoscience & nanotechnologyARPES01 natural sciencesSettore FIS/03 - Fisica Della MateriaComputer Science ApplicationsComputational physicsX-ray photoelectron spectroscopyTDDFTIonization0103 physical sciencesMonolayerDensity functional theoryPhysical and Theoretical Chemistry010306 general physics0210 nano-technology
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Calculations Yb [Dataset]

2022

Orca outputs of TDDFT and DFT calculations on a Yb complex Archivos OUT. Abrir con Windows Notepad, WordPad, TextEdit o Text editor. Archivos OUT. Abrir con Windows Notepad, WordPad, TextEdit o Text editor.

TDDFT DFT Calculation with OrcaUNESCO::QUÍMICAcalculations
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Dynamical amplification of electric polarization through nonlinear phononics in 2D SnTe

2020

Ultrafast optical control of ferroelectricity using intense terahertz fields has attracted significant interest. Here we show that the nonlinear interactions between two optical phonons in SnTe, a two-dimensional in-plane ferroelectric material, enables a dynamical amplification of the electric polarization within subpicoseconds time domain. Our first-principles time-dependent simulations show that the infrared-active out-of-plane phonon mode, pumped to nonlinear regimes, spontaneously generates in-plane motions, leading to rectified oscillations in the in-plane electric polarization. We suggest that this dynamical control of ferroelectric material, by nonlinear phonon excitation, can be ut…

Terahertz radiationPhononPhysics::Optics02 engineering and technology01 natural sciences7. Clean energySettore FIS/03 - Fisica Della MateriaCondensed Matter::Materials ScienceTDDFT0103 physical sciencesGeneral Materials ScienceTime domain010306 general physicsPhysicsFerroelecrtricityCondensed matter physics021001 nanoscience & nanotechnologyFerroelectricityComputer Science ApplicationsPolarization densityNonlinear systemMechanics of MaterialsModeling and Simulation0210 nano-technologyUltrashort pulseExcitation
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Quantum correlation of electron and ion energy in the dissociative strong-field ionization of H2

2023

We report on the strong field ionization of H2 by a corotating two-color laser field. We measure the electron momentum distribution in coincidence with the kinetic energy release (KER) of dissociating hydrogen molecules. In addition to a characteristic half-moon structure, we observe a low-energy structure in the electron momentum distribution at a KER of about 3.5 eV. We speculate that the outgoing electron interacts with the molecular ion, despite the absence of classical recollisions under these conditions. Time-dependent density functional theory simulations support our conclusions.

Time resolved photoelectron spectroscopy. Real time TDDFTGeneral Physics and AstronomySettore FIS/03 - Fisica Della MateriaPhysical Review Research
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Attosecond magnetization dynamics in non-magnetic materials driven by intense femtosecond lasers

2023

Irradiating solids with ultrashort laser pulses is known to initiate femtosecond timescale magnetization dynamics. However, sub-femtosecond spin dynamics have not yet been observed or predicted. Here, we explore ultrafast light-driven spin dynamics in a highly non-resonant strong-field regime. Through state-of-the-art ab-initio calculations, we predict that a non-magnetic material can be transiently transformed into a magnetic one via dynamical extremely nonlinear spin-flipping processes, which occur on attosecond timescales and are mediated by a combination of multi-photon and spin-orbit interactions. These are non-perturbative non-resonant analogues to the inverse Faraday effect that buil…

Ultrafest magnetismCondensed Matter - Mesoscale and Nanoscale PhysicsTDDFTMechanics of MaterialsModeling and SimulationMesoscale and Nanoscale Physics (cond-mat.mes-hall)Physics::OpticsFOS: Physical sciencesGeneral Materials ScienceSettore FIS/03 - Fisica Della MateriaPhysics - OpticsComputer Science ApplicationsOptics (physics.optics)
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Modelling the effect of nuclear motion on the attosecond time-resolved photoelectron spectra of ethylene

2014

arXiv:1403.5408

attosecond pump probeAttosecondFOS: Physical sciencesElectronmedicine.disease_cause01 natural sciencesSpectral lineSettore FIS/03 - Fisica Della Materianuclear motionTDDFTPhysics - Chemical Physics0103 physical sciencesmedicinePhysics::Atomic and Molecular ClustersMoleculePhysics - Atomic and Molecular ClustersPhysics::Chemical Physics010306 general physicsPhysicsChemical Physics (physics.chem-ph)010304 chemical physicsTRPESTime-dependent density functional theoryCondensed Matter PhysicsAtomic and Molecular Physics and Optics3. Good healthExtreme ultravioletFemtosecondAtomic physicsAtomic and Molecular Clusters (physics.atm-clus)Ultraviolet
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Octopus, a computational framework for exploring light-driven phenomena and quantum dynamics in extended and finite systems

2020

Over the last few years, extraordinary advances in experimental and theoretical tools have allowed us to monitor and control matter at short time and atomic scales with a high degree of precision. An appealing and challenging route toward engineering materials with tailored properties is to find ways to design or selectively manipulate materials, especially at the quantum level. To this end, having a state-of-the-art ab initio computer simulation tool that enables a reliable and accurate simulation of light-induced changes in the physical and chemical properties of complex systems is of utmost importance. The first principles real-space-based Octopus project was born with that idea in mind,…

spectroscopyPhotonelectronic-structure calculationsComputer sciencespectraQuantum dynamicsmolecular-dynamicsComplex systemGeneral Physics and AstronomyFOS: Physical sciences010402 general chemistryspin01 natural sciencesSettore FIS/03 - Fisica Della MateriaEngineeringTDDFTreal-space0103 physical sciencesoctopusgeneralized gradient approximationPhysical and Theoretical Chemistrydensity-functional theoryMassively parallelQuantumChemical Physicsreal time010304 chemical physicsComputational Physics (physics.comp-ph)scientific software0104 chemical sciencestotal-energy calculationsphysics.comp-phPhysical SciencesChemical Sciencespolarizable continuum modelState of matterSystems engineeringLight drivenDensity functional theoryPhysics - Computational Physics
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Real-space quantum transport in two-dimensional nanostructures in magnetic fields

2013

stadiumajasta riippuva tiheysfunktionaaliteoriaTDDFTkvanttikaaostime-depedent density-functional theoryquantum dotAharonov-Bohmkvanttirengasquantum ringstadionkvanttipistequantum chaos
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