Search results for "Quantum wires"

showing 3 items of 13 documents

Isolated self-assembled InAs/InP(001) quantum wires obtained by controlling the growth front evolution

2007

6 páginas, 5 figuras. In this work we explore the first stages of quantum wire (QWR) formation studying the evolution of the growth front for InAs coverages below the critical thickness, θc, determined by reflection high energy electron diffraction (RHEED). Our results obtained by in situ measurement of the accumulated stress evolution during InAs growth on InP(001) show that the relaxation process starts at a certain InAs coverage θRθR this ensemble of isolated nanostructures progressively evolves towards QWRs that cover the whole surface for θ = θc. These results allow for a better understanding of the self-assembling process of QWRs and enable the study of the individual properties of In…

Single quantum wiresWork (thermodynamics)Materials scienceNanostructureReflection high-energy electron diffractionCondensed matter physicsMechanical EngineeringQuantum wireBioengineeringGeneral ChemistryCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter::Materials ScienceCrystallographyReflection (mathematics)Electron diffractionMechanics of MaterialsGeneral Materials ScienceElectrical and Electronic EngineeringMolecular beam epitaxyQuantumMolecular beam epitaxyNanotechnology
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Electron Fabry-Perot interferometer with two entangled magnetic impurities

2007

We consider a one-dimensional (1D) wire along which single conduction electrons can propagate in the presence of two spin-1/2 magnetic impurities. The electron may be scattered by each impurity via a contact-exchange interaction and thus a spin-flip generally occurs at each scattering event. Adopting a quantum waveguide theory approach, we derive the stationary states of the system at all orders in the electron-impurity exchange coupling constant. This allows us to investigate electron transmission for arbitrary initial states of the two impurity spins. We show that for suitable electron wave vectors, the triplet and singlet maximally entangled spin states of the impurities can respectively…

Statistics and ProbabilityQUANTUM WIRESQuantum decoherenceSpin statesFOS: Physical sciencesGeneral Physics and AstronomyElectron01 natural sciences010305 fluids & plasmasMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesSCATTERINGSinglet state010306 general physicsMathematical PhysicsPhysicsCoupling constantINTERFERENCEQuantum PhysicsCondensed matter physicsCondensed Matter - Mesoscale and Nanoscale PhysicsScatteringStatistical and Nonlinear Physics3. Good healthModeling and SimulationCondensed Matter::Strongly Correlated ElectronsQuantum Physics (quant-ph)Electron scatteringStationary state
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Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange

2004

The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.

Work (thermodynamics)Materials scienceOptical fiberPhysics and Astronomy (miscellaneous)Substrate (electronics)Optoelectronic deviceslaw.inventionEmissionOptical fibreslawIndium compoundsArsenic compoundsSize effectPhosphorus compoundsRange (particle radiation)business.industrySelf-assemblyWavelengthSemiconductor quantum wiresOptoelectronicsSelf-assemblybusinessSurface reconstructionLayer (electronics)Surface reconstruction
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