Search results for "Spin-flip"

showing 3 items of 23 documents

Intravalley spin-flip relaxation dynamics in single-layer WS2

2019

Two-dimensional Transition Metal Dichalcogenides (TMDs) have been widely studied because of the peculiar electronic band structure and the strong excitonic effects [1]. In these materials the large spin-orbit coupling lifts the spin degeneracy of the valence (VB) and the conduction band (CB) giving rise to the A and B interband excitonic transitions. In monolayer WS2, the spins of electrons in the lowest CB and in the highest VB at K/K' point of the Brillouin zone are antiparallel resulting in an intravalley dark exciton state at a lower energy than the bright exciton, see left panel of Fig.1. On the one hand, the presence of dark excitons has been revealed indirectly from the observation o…

PhysicsValence (chemistry)Condensed matter physicsSpinsScatteringExciton02 engineering and technologyElectronCondensed Matter::Mesoscopic Systems and Quantum Hall Effect021001 nanoscience & nanotechnology01 natural sciencesBrillouin zoneCondensed Matter::Materials Science0103 physical sciencesSpin-flip010306 general physics0210 nano-technologyElectronic band structure
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Radiative 2D Shocks, Super-Eddington Disks and Jets around Black Holes

2005

It is well known that rotating inviscid accretion flows with adequate injection parameters around black holes could form shock waves close to the black holes, after the flow passes through the outer sonic point and can be virtually stopped by the centrifugal force. Such shock waves in 2D accretion flows are examined by 2D radiation hydrodynamical calculations. We also examine super‐Eddington accretion disks with 15 ṀE around black holes, focusing on a small collimation degree of the jet and a large mass‐outflow rate observed in the X‐ray source SS 433.

Shock wavePhysicsGeneral Relativity and Quantum CosmologyBinary black holeIntermediate-mass black holeAstrophysics::High Energy Astrophysical PhenomenaRadiative transferStellar black holeAstrophysicsSpin-flipAstrophysics::Galaxy AstrophysicsGamma-ray burst progenitorsAccretion (astrophysics)AIP Conference Proceedings
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Spin relaxation in Cu and Al spin conduits

2014

We study the spin relaxation in Al and Cu spin conduits embedded in non-local spin valve nanostructures. Measuring the key spin transport properties, we determine the spin and charge diffusion constants as well as the spin flip time. By varying the temperature, we find that the maximum of the non-local spin resistance change occurs at finite temperatures with a clear difference between Al and Cu. In particular, we find that the maximum of the non-local spin signal in Al is less pronounced and occurs at lower temperatures compared to Cu suggesting that the self-passivating Al surface plays a role. Having fabricated devices with both materials in identical processes, we can attribute the diff…

Spin polarizationCondensed matter physicsChemistrySpin valveSurfaces and InterfacesZero field splittingCondensed Matter PhysicsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsSpin iceSpin waveMaterials ChemistryCondensed Matter::Strongly Correlated ElectronsSpin-flipElectrical and Electronic EngineeringQuantum spin liquidSpin-½physica status solidi (a)
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