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Showing 1 to 19 of 19 for “"heterointerfaces"”.
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Functional heterointerfaces via electromodulation spectroscopy
… on the electronic structures across these heterointerfaces are performed with the combined use of electromodulation and photoemission spectroscopic techniques. Electromodulation and ultraviolet photoemission spectroscopic techniques enable direct determination of the surface work functions …
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Nanoscale Characterisation of Heterointerfaces in 2D Materials
… for performing nanoscale characterisation of heterointerfaces in 2D materials. We first examine interfaces in 2D lateral heterostructures of monolayer transition metal dichalcogenides (1L-TMDs). Studies on the synthesis of these structures have shown a range of interface widths can occur, …
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Quasi-two-dimensional phenomena at AlGaAs-GaAs heterointerfaces, multiple quantum wells and modulation-doped structures
… describes a subset of phenomena at AIGaAs-GaAs heterointerfaces related to multiple quantum wells and modulation-doped structures. In the first section. two important results concerning multiple quantum well systems are described: optical absorption coefficients and exciton oscillator strengths …
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First Principles Studies of Magnetic Oxides, Spin-Driven Ferroelectricity, and the Effect of Polarization in the Chemistry of Functional Heterointerfaces
Achieving accurate description and understanding of the chemical and physical properties of complex materials enables the further development of their technological applications. Employing density functional theory (DFT) with rotationally invariant Hubbard corrections, we present an extensive study …
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Quasi-Two-Dimensional Phenomena at Aluminum-Gallium - Arsenide - Gallium-Arsenide Heterointerfaces: Multiple Quantum Wells and Modulation-Doped Structures (Superlattice, Modfet, Semiconductors)
… describes a subset of phenomena at AlGaAs-GaAs heterointerfaces related to multiple quantum wells and modulation-doped structures. In the first section, two important results concerning multiple quantum well systems are described: optical absorption coefficients and exciton oscillator strengths …
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III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes
… layers, abrupt GaAs-AlGaAs as well as dopant heterointerfaces and silicon-dopant spikes. A consistently high quality of epitaxial GaAs and AlGaAs is achievable with controllable silicon, tellurium and zinc doping on both material systems. The OMVPE system is sufficiently calibrated to grow …
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Theoretical investigations of reduced size effects in gallium-arsenide and heterostructure electron devices
… fluctuations and boundary conditions at heterointerfaces are examined, specifically, electron transport models are developed for the effects of impurity fluctuations, contacts, and heterostructure barriers. The investigations are carried out for the GaAs - Al$\sb{\rm x}$Ga$\sb{\rm 1-x}$As …
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Optical properties and carrier transport in Si/ Si1-xGex nanostructures
… of an abrupt and defect-free Ge NW/Si substrate heterointerfaces. From the measurements on Si/SiGe cluster superlattices (SLs) where SiGe clusters are vertically aligned due to strain-induced self-organization, a series of step-like structures are observed in the I-V characteristics obtained …
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Templated self-assembly of multiferroic nanocomposites
… naturally forming numerous such heterointerfaces. These provide a rich playground for studying interfacial effects, which could be used in future devices, and the self-assembly promises cheap arid high throughput manufacturing providing it can be integrated into useful …
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Plastic Relaxation of Highly Tensile Strained (100) Ge/InGaAs Heterostructures
… may inevitably be present at and#949t-Ge/InGaAs heterointerfaces in practical devices, and that the effect of MDs on optoelectronic performance must be better understood.
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Mechanophore activation at heterointerface and surface crowdedness as a determining factor
… polymers. However, behavior of mechanophores at heterointerfaces is particularly interesting, as interfaces in composite materials are often the weakest point where damage-reporting and self-healing are applicable. To achieve this goal, a model system was constructed to allow facile synthesis and …
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Vertical cavity surface emitting lasers.
… Methods of disruption of the AlAs / GaAs heterointerfaces have been used to reduce the operating voltage. The completed designs use 200A intermediate layers containing 30 or 50% aluminium or a superlattice graded region simpler than that used in previous designs. The effectiveness acceptor …
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Exploiting polar interfaces for photocatalytic water splitting: application to the anatase-cuprous oxide heterojunction
… we successfully establish that polar thin-film heterointerfaces can be a useful system for catalysis, and demonstrate that computational modeling of these metal oxide systems can help guide experimental work in order to deterministically control surface orientation and chemistry for optimized …
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Investigation of Threshold Voltage Instability in Normally Off GaN on Si HEMT
… (GaN) in particular, with its ability to form heterointerfaces naturally forms a high mobility 2-dimensional electron gas (2-DEG) at hetero interfaces like AlGaN/GaN making it an apt candidate for making power devices with lower on state resistance and higher frequency of operation. With the …
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Electronic properties of metal-organic and organic-organic interfaces studied by photoemission and photoabsorption spectroscopy
… - The electronic properties of the organic heterointerfaces between fullerite and pristine copper phthalocyanine were studied. Both interfaces, CuPc/C60 and C60/CuPc, were found to be non-reactive with pronounced shifts of the vacuum level pointing to the formation of an interfacial dipole …
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Novel materials, computational spectroscopy, and multiscale simulation in nanoscale photovoltaics
… requiring the presence of semiconductor heterointerfaces within the active layer to dissociate excitons and generate charge carriers. Such interfaces are known as donor-acceptor (D-A) interfaces, and their presence leads to correlated exciton and charge dynamics in nanoscale PV. Material …
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Enhancing the mechanical and chemical integrity of Ag/ZnO-based transparent and conductive thin film coatings: an atomistic modelling study
The commercialisation of ZnO/Ag/ZnO based flexible TCEs (transparent conductive electrodes) is still hindered by the adhesion between Ag and ZnO that results in a weak Ag/ZnO interface. This weakness is further reflected by the observed dewetting of Ag on ZnO. Optical coatings containing these …
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INVESTIGATION OF PHASE TRANSFORMATIONS IN TRANSITION METAL DICHALCOGENIDES DURING SYNTHESIS AND POST GROWTH
… as well as stabilization of phases across TMDC heterointerfaces. This phase engineering could be important for a range of applications, including catalysis and next-generation electronic and optical devices.
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Understanding and engineering electronic and optoelectronic properties of 2D materials and their interfaces
… of the underlying physics at the 2D vdW heterointerfaces, the possibility of a black phosphorus (BP)-MoS2 vertical heterostructure as an ultrathin channel material for high-performance 2D (opto)electronic devices is studied. CVD-synthesized MoS2 and micromechanically exfoliated BP …