Search results for " MoS2"

showing 2 items of 2 documents

Spinorial formulation of the GW-BSE equations and spin properties of excitons in two-dimensional transition metal dichalcogenides

2021

In many paradigmatic materials, such as transition metal dichalcogenides, the role played by the spin degrees of freedom is as important as the one played by the electron-electron interaction. Thus an accurate treatment of the two effects and of their interaction is necessary for an accurate and predictive study of the optical and electronic properties of these materials. Despite the fact that the GW-BSE approach correctly accounts for electronic correlations, the spin-orbit coupling effect is often neglected or treated perturbatively. Recently, spinorial formulations of GW-BSE have become available in different flavors in material-science codes. However, an accurate validation and comparis…

PhysicsWork (thermodynamics)Settore FIS/03ExcitonDegrees of freedom (physics and chemistry)02 engineering and technology021001 nanoscience & nanotechnologyCoupling (probability)01 natural sciencesPartícules (Física nuclear)Coupling effectTransition metalQuantum mechanics0103 physical sciencesmany-body perturbation theory non collinear spin spin-orbit coupling Hedin's equations GW BSE DFT MoS2 electronic properties optical properties010306 general physics0210 nano-technologyMaterialsMixing (physics)Spin-½
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Strongly Coupled Coherent Phonons in Single-Layer MoS 2

2019

We present a transient absorption setup combining broadband detection over the visible-UV range with high temporal resolution ($\sim$20fs) which is ideally suited to trigger and detect vibrational coherences in different classes of materials. We generate and detect coherent phonons (CPs) in single layer (1L) MoS$_2$, as a representative semiconducting 1L-transition metal dichalcogenide (TMD), where the confined dynamical interaction between excitons and phonons is unexplored. The coherent oscillatory motion of the out-of-plane $A'_{1}$ phonons, triggered by the ultrashort laser pulses, dynamically modulates the excitonic resonances on a timescale of few tens fs. We observe an enhancement by…

ramanspectroscopyPhononExcitonGeneral Physics and AstronomyFOS: Physical sciences02 engineering and technologyApplied Physics (physics.app-ph)thz phonons010402 general chemistry01 natural sciencesMolecular physicssymbols.namesakephotoinduced bandgap renormalizationtransient absorption spectroscopyUltrafast laser spectroscopyMesoscale and Nanoscale Physics (cond-mat.mes-hall)General Materials Sciencepulsesexciton−phonon interactionPhysicsab initio calculationCondensed Matter - Materials ScienceCondensed Matter - Mesoscale and Nanoscale Physicstransition metal dichalcogenidesgrapheneGeneral Engineeringmonolayer mos2ResonanceMaterials Science (cond-mat.mtrl-sci)excitationmonodynamicsPhysics - Applied Physics021001 nanoscience & nanotechnology0104 chemical sciencesAmplitudeOrders of magnitude (time)coherent phononsexciton-phonon interactionsymbols0210 nano-technologyRaman spectroscopyExcitationACS Nano
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