Characteristics of strained GaAs_1−ySb_y (0.16 ≤ y ≤ 0.69) quantum wells on InP substrates

Abstract

Pseudomorphic GaAs 1−y Sb y quantum wells with 0.16 y 0.69 on (0 0 1) InP substrates have been grown using metal-organic chemical vapour deposition. High resolution x-ray diffraction and transmission electron microscopy analysis are used to quantify the layer thicknesses and compositions. Studies of the optical properties suggest that a transition from type-I to type-II band alignment occurs at an antimony concentration of approximately y = 0.30. The interband optical transition energies simulated using a ten-band k • p Hamiltonian are compared with the experimental values deduced from photoluminescence spectroscopy. The valence band offset bowing parameter is evaluated in the context of the experimental transition energies. For low Sb-contents, reasonable agreement (<7% deviation) is achieved between theory and experiment for the primary optical transitions. However, at higher Sb-content, there is significant deviation between the measured transition energies and the k • p based theory, possibly a result of a non-ideal interface and/or heterogeneous ternary well.

Synthesis and electron transfer property of sulfhydryl-containing multi-walled carbon nanotube/gold nanoparticle heterojunctions

“…One-dimensional metal/semiconductor heterojunction nanomaterials are of key importance because of their novel structures, unique electrical and optical properties and central roles in fabricating electronic nanodevices [1,2]. In nanodevices, heterojunction nanomaterials can effectively control electron, positive hole and exciton transmission and thus possess a unique Coulomb blockade effect [3], Schottky diode behaviour [4], Ohmic contact property [5] and photoluminescence property [6], using which singleelectron transistors, electronic and optoelectronic devices, photodetection devices, biological/chemical sensors, logic 1 Author to whom any correspondence should be addressed. circuits, etc have been successfully manufactured.…”

MOVPE growth of antimonide-containing alloy materials for long wavelength applications

“…The extension of the GaAs 1Ày Sb y alloy system by the introduction of N has been studied by several groups for growth on GaAs [38,39], GaSb [40] and InP [7,41,42] substrates. The addition of N leads to a substantial band-bowing in the GaSb 1Àz N z [43], and it is seen as an alternative material for InGaAsN.…”

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