We have used transient terahertz photoconductivity measurements to assess the efficacy of two-temperature growth and core-shell encapsulation techniques on the electronic properties of GaAs nanowires. We demonstrate that two-temperature growth of the GaAs core leads to an almost doubling in charge-carrier mobility and a tripling of carrier lifetime. In addition, overcoating the GaAs core with a...

Multilayers of InGaAs nanostructures are grown on GaAs(210) by molecular beam epitaxy. With reducing the thickness of GaAs interlayer spacer, a transition from InGaAs quantum dashes to arrow-like nanostructures is observed by atomic force microscopy. Photoluminescence measurements reveal all the samples of different spacers with good optical properties. By adjusting the InGaAs coverage, both on...

We present the study of n-GaAs surface modification by electrochemical etching in different electrolyte compositions. The possibility forming micromorphology types on identical GaAs samples, particular crystallographic, defective-dislocation, and isotope interfaces, was investigated.

P-type GaAs/AlAs distributed Bragg mirrors have been grown using molecular beam epitaxy on (100) and (311)A GaAs substrates in a similar conditions. A comparison of I-V measurements shows that the resistance of the ungraded mirrors grown on the (311)A substrate is 35 times lower than those grown on the (100) substrate with similar structure. The effective barrier heights for both (311 )A and (1...

We present a novel GaAs metal–semiconductor field-effect transistor (MESFET) with InGaP/GaAs multiple quantum barrier (MQB) capping and buffer layers. The MQB structure with (29; 6, 5, 7; 8, 8, 1; 6, 5, 7; 29) periodic stacks was designed to increase effective-potential-barrier height. We demonstrate that, by using the InGaP/GaAs MQB capping layer, the gate Schottky barrier performance and gate...

THz radiation is detected by a low-temperature-grown GaAs ~LT-GaAs! photoconductive antenna probed with a 1.55 mm probe laser. The detection efficiency is found to be approximately 10% of that obtained with a 780 nm probe. From the nonquadratic dependence of photoconductivity on laser intensity, two-step photoabsorption mediated by midgap states in LT-GaAs is suggested, instead of the two-photo...

Phonon-assisted exciton transitions in spherical GaAs nanocrystals embedded in SiO2 matrices have been studied by means of selective excitation spectroscopy. The optical and acoustic phononassisted optical transitions appear in the photoluminescence excitation, photoluminescence linenarrowing, and photoluminescence hole-burning spectra at low temperatures. Both direct (zerophonon) and phonon-as...

Up to now, many efforts have been continuously channeled toward the development of oxidation techniques on the III-V compounds for GaAs-based device application, which include thermal oxidation [1-7], chemical anodization [8-12], photochemical oxidation [13-16], plasma oxidation [17-20], Ga2O3 grown by molecular beam epitaxy (MBE) [21-23], Al2O3 grown by atomic layer deposition (ALD) [24], oxid...

In this paper, the polarization response of a GaAs based two-photon absorption microcavity photodetector has been studied. The deviation in the dependence of the detector response from that of bulk GaAs is shown to be due to the birefringence of the cavity. A theoretical model based on the convolution of the cavity birefringence and the polarization dependence of two-photon absorption in GaAs i...

AlGaAs/GaAs heterojunction bipolar transistors (HBTs) are used for digital and analog microwave applications with frequencies as high as Ku band. HBTs can provide faster switching speeds than silicon bipolar transistors mainly because of reduced base resistance and collector-to-substrate capacitance. HBT processing requires less demanding lithography than GaAs FETs, therefore, HBTs can cost les...