We demonstrate the first long-wavelength (Xc= 20 pm) quantum WN infrared photodetector using non-lattice matched InxGaj-xAs/GaAs materials system. High optical gains (low capture probabilities) were achieved by using GaAs as a barrier material in this system. The dctcctivity has been found to be comparable to those achieved with the usual lattice matched GaAs/AlxGal-XAS detectors.

Through the utilization of index-matched GaAs immersion lens techniques, we demonstrate a record extinction (12%) of a far-field focused laser beam by a single InAs/GaAs quantum dot. This contrast level enables us to report for the first time resonant laser transmission spectroscopy on a single InAs/GaAs quantum dot without the need for phase-sensitive lock-in detection.

This paper focuses on recent results on the optical properties of self-assembled quantum dots involving typeI InGaAs/GaAs and type-II InP/GaAs interfaces. In the first part, we focus on the InGaAs/GaAs quantum dots, that were used to study the influence of a two-dimensional electron gas on the optical emission of single quantum dots. In the second part, we present the results on type-II InP/GaA...

5:40pm NM-MoE1 Interfacial Chemistry between gas-phase molecules and GaAs surfaces: morphology dependence, Sylwia Ptasinska, XQ. Zhang, University of Notre Dame A detailed understanding of molecular interactions at the interface of twodimensional GaAs systems under ultra-high vacuum (UHV) conditions has been achieved over the decades. While research on the understanding of such interactions wit...

We report organometallic vapor-phase epitaxy ~OMVPE! growth and optical characteristics of 1.17–1.20 mm double-heterostructure laser diodes with three Ga0.7In0.3N0.003As0.997 ~7 nm!/GaAs~10 nm! quantum wells ~GaInNAs/GaAs QWs!. Three GaInNAs/GaAs QWs were successfully grown by OMVPE using dimethylhydrazine as the N precursor. Strong room-temperature photoluminescence at the 1.17–1.19 mm regime ...

Evidence for electron accumulation in the ZnSe side of n-ZnSe/n-GaAs heterostructures is presented. An n-GaAs buffer layer, approximately 1 pm thick, grown with low 1015 electronic concentration on a semi-insulating (100) GaAs substrate is fully depleted of electrons when an additional epilayer of nZnSe is grown on top of it. The n-GaAs epilayer electron concentration is restored when the ZnSe ...

Single-crystal atomic-layer-deposited (ALD) Y2O3 films 2 nm thick were epitaxially grown on molecular beam epitaxy (MBE) GaAs(001)-4 ˆ 6 and GaAs(111)A-2 ˆ 2 reconstructed surfaces. The in-plane epitaxy between the ALD-oxide films and GaAs was observed using in-situ reflection high-energy electron diffraction in our uniquely designed MBE/ALD multi-chamber system. More detailed studies on the cr...

the possibility of terahertz generation has been investigated from a photoconductive switch based on gaas, gated by a femtosecond laser. the emission properties of photoconductive antenna (pca) with low-temperature-grown (lt) gaas have been studied. in such gaas materials presence of the charged defects induces a redistribution of the electric field between the antenna electrodes. this effect h...

High efficiency GaAs concentrator cells are useful for numerous applications requiring isolated power and voltage, or transmission of power without electromagnetic interference. This paper concerns the characteristics of GaAs concentrator cells illuminated by high-intensity laser beams. The objectives of this study are to identify and understand the mechanisms which limit the performance of GaA...

Gallium arsenide (GaAs), a technologically and economically important semiconductor, is widely utilized in both military and commercial applications. This chemical is a potential health hazard as a carcinogen and immunotoxicant. We previously reported that macrophages at the exposure site exhibit characteristics of activation. In vitro culture of macrophages with GaAs fails to recapitulate the ...