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Showing 1 to 20 of 27 for “"MQW"”.
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Synchrotron radiation-based characterization of GaN- based MQW structures and strongly correlated materials
… properties of GaN-based multiple quantum well (MQW) structures grown on trapezoidal shaped GaN ridges. Results where interpreted within the framework of vapor-phase diffusion and surface-migration effects during the metalorganic vapor phase epitaxial growth. The relatively short diffusion length …
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Towards multiple quantum well optically pumped far infrared lasers
… based on GaAs/AlGaAs multiple quantum well (MQW) structures are a potential coherent source in the far infrared (FIR) wavelengths. The FIR (~ 30 to 300 µm) is a region within the electromagnetic spectrum that has seen relatively little development. No practical solid-state lasers have been …
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Material processing of quantum well infrared photodetectors
… (RTA) GaAs/AlGaAs multiple quantum well (MQW) infrared (IR) photodetectors (QWIPs) epitaxially grown on GaAs and Si substrates is presented. The advances in epitaxial growth allow the precise control of the dimensions, doping, and matrix concentration of the MQW. Therefore, the design of a …
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Structural and Optical Properties of Gan-Based Heterostructures Grown by Plasma-Assisted Molecular Beam Epitaxy
$\rm Al\sb{0.2}Ga\sb{0.8}$N-GaN MQWs grown by PAMBE demonstrate their feasibility for optical device application. The excitonic transition properties observed from the MQW structures suggest the implementation of very thin, $<$50 A, quantum wells for high efficiency and emission uniformity.
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Growth of Gallium Nitride-Based Nitride Semiconductors by PAMBE for Development of Optoelectronic and Microelectronic Devices
… diode (HJ LED), multi-quantum well (MQW) LED, and buried gate junction field effect transistor (BGJFET), are fabricated by PAMBE and their characteristics are demonstrated to show the high quality of GaN-based nitride films grown by PAMBE.
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Characterisation and simulation of InAs/InAsSb structures for mid-infrared LEDs
… superlattice (SLS) and multiple quantum well (MQW) structures of low antimony content (Sb = 3.7 – 13.5 %) grown by MBE on InAs substrates were compared. These structures were characterised by XRD and TEM imaging. Band structure simulations highlighted the effects of changing QW antimony content …
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Excitonic optical nonlinearities in semiconductors and semiconductor microstructures.
… and ZnSe, GaAs/AlGaAs multiple-Quantum-Wells (MQW's), and finally, quantum-confined CdSe-doped glasses. The microscopic origins and magnitudes of the optical nonlinearities of bulk GaAs and ZnSe were investigated and the exciton recovery time in ZnSe was measured. A comparison with a plasma …
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Growth and Behaviors of InN/GaN Multiple Quantum Wells by Plasma-Assisted Molecular Beam Epitaxy
… problems. InN/GaN multiple quantum wells (MQWs) and super lattices (SLs) are expected to be promising alternatives to random InGaN alloys since in principle they can achieve the equivalent band gap of InGaN random alloys with arbitrarily high In-content and at the same time bypass many …
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Fabrication and Characterization of Optoelectronics Devices Based on III-V Materials for Infrared Applications by Molecular Beam Epitaxy
… strain-compensated multiple-quantum-well (SCMQW) lasers on InP (100), InGaAsNSb/GaAs quantum wells (QWs) grown on GaAs (411)A substrates and mid-infrared InGaAsSb lasers with digitally grown tensile-strained AlGaAsSb barriers. Type-II InAs/GaSb superlattice IR detectors with various spectral …
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Investigation of intracavity phase interferometry applied to nano-metrology
… laser, mode-locked by a multiple quantum wells (MQW) saturable absorber. The presence of a solid state saturable absorber introduced a dead band in the beat note response of the system. A new coupling between group and phase velocity was discovered experimentally, and explained through …
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Molecular beam epitaxy of InAsP graded buffers: From mid-infrared quantum wells to InAs virtual substrates with low threading dislocation density
… buffers. Strain-balanced multiple quantum well (MQW) structures grown with In0.54Ga0.46 barriers demonstrated much higher photoluminescence intensity than structures with InAs0.25P0.75 barriers. Both structures showed reduced misfit dislocation density in comparison to MQW structures grown …
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The Effect of Polarization and InGaN Quantum Well Shape in Multiple Quantum Well Light Emitting Diode Heterostructures
… profile within InGaN multiple quantum well (MQW) devices shows much smoother and delayed transitions indicative of indium diffusion and drift during common atomic deposition techniques (e.g. molecular beam epitaxy, chemical vapor deposition). In this case the InGaN square QW approximation may …
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Theory and Modelling of Wavelength Tunable Laser Transmitters With Enhanced Tuning Range and Their Modulation Performance
… tuning in bulk and Multiple Quantum Well (MQW) TLDs was also addressed and it was found that the power drop can be delayed at latter stages of the tuning range by carefully selecting the Lorentzian lineshape of the gain spectrum. A power stabilisation was realised with continuous tuning. A …
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Characterisation of polar (0001) and non-polar (11-20) ultraviolet nitride semiconductors
… grown on AlN template, and nonpolar GaN/AlGaN MQWs grown on a-plane GaN template. The results are based primarily on transmission electron microscopy (TEM), cathodoluminescence in the scanning electron microscope (SEM-CL), high-resolution X-ray diffraction (HRXRD) and atomic force microscopy …
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Micro-cleaved ridge lasers for optoelectronic integration on silicon
… thin (-6 pm) InP-based multiple quantum well (MQW) ridge laser platelets emitting at a wavelength of 1550 nm have been manufactured and integrated by metal-to-metal bonding onto silicon substrates. These laser platelets can be thought of as freestanding optoelectronic building blocks that can …
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Polarization multiplexed photonic integrated circuits for 100 Gbit/s and beyond
… The EAMs make use of multi-quantum well (MQW) layers, thin sheets of semiconductor that break the symmetry of the InP crystal. The electronic and optoelectronic effects in MQW-based EAMs are studied to verify that the proposed DP EAM can indeed be demonstrated with good performance. In …
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III-nitride Semiconductors Grown By Plasma Assisted Molecular Beam Epitaxy
… conditions, a lateral geometry GaN/A1GaN MQW-based photodetector was fabricated. It exhibited a flat and narrow spectral response in the range of 297~352 nm in the backillumination configuration.
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Band anti-crossing modelling and characterization of multi quantum well gainnas for photovoltaic application
… /GaAs multi-quantum-well (MQW) p-i-n diode has reported that it is able to operate in near-infrared applications (800-1100nm). Nevertheless, there is no elucidations on the effect of indium (In) and nitrogen (N) fractions on electronic band transition, the localisation …
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Wide-Bandgap III-Nitride Tunnel Junctions and Novel Approaches towards Improving Optoelectronic Devices
… tunnel-contacted InGaN multi-quantum well (MQW) solar cells and LEDs are fabricated, which demonstrate the tunnel junctions are compatible in both forward and reverse bias applications. Finally, ultra-wide-bandgap AlGaN material is synthesized to enable ultraviolet optoelectronics. …
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Efficiency droop mitigation and quantum efficiency enhancement for nitride Light-Emitting Diodes
… of quantum wells (QWs, 2 nm-thick) in multi-QW (MQW) LED structures due to the better material quality and higher density of states. Additionally, increased thickness of stair-case electron injectors (SEIs) has been demonstrated to greatly mitigate electron overflow without sacrificing material …
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