WE PRESENT THE MOLECULAR BEAM EPITAXY FABRICATION AND OPTICAL PROPERTIES OF COMPLEX GAAS NANOSTRUCTURES BY DROPLET EPITAXY: concentric triple quantum rings. A significant difference was found between the volumes of the original droplets and the final GaAs structures. By means of atomic force microscopy and photoluminescence spectroscopy, we found that a thin GaAs quantum well-like layer is deve...

In the spectra of photoemission quantum yield p-GaAs(Cs,O) measured in reflection geometry, a peak was found at photon energy lower than band gap GaAs. It is shown that appearance due to trapping weakly absorbed radiation, which scatters diffusely on rough back face epitaxial structure. Possible microscopic mechanisms are discussed: Franz-Keldysh effect surface electric field and adsorption-mod...

Gallium arsenide is an outstanding nonlinear optical material, thanks to its high second-order nonlinear coefficient, wide transparency in the infrared, and possibility of integration with sources. However, phase matching for nonlinear frequency conversion is difficult to achieve in this isotropic, highly dispersive semiconductor. Although quasimatching by domain reversal was recently demonstra...

Using Auger electron spectroscopy and x-ray photoelectron spectroscopy we show that the unpinned GaAs is covered by a Ga203 layer with only small amounts of species containing arsenic. This oxide is formed by the consumption of GaAs during the unpinn ing treatment. We believe that it is this oxide that passivates the surface, allowing it to remain near flatband for several hours in room air. Th...

Progress in processing low-loss quasi-phase-matched gallium arsenide crystals makes it possible to benefit from their excellent nonlinear properties in practical mid-infrared sources. This paper addresses both crystal growth aspects and the most recent device demonstrations. ©2012 Optical Society of America OCIS codes: (190.4400) Nonlinear optics, materials; (140.3070) Infrared and far-infrared...

We have investigated the optical properties of unstrained GaAs/AlxGa1−xAs quantum dot/well systems with the aim of studying the influence of confinement on the effective exciton mass, as determined from the photoluminescence line shift in high magnetic fields 50 T . The effective exciton mass is found to be more than twice the value for bulk GaAs. We attribute this to an enhanced nonparabolicit...

Recent developments in mobile, cloud, and graphics processing technologies have enabled mobile cloud gaming, a gaming model where players use mobile devices to play graphics-intensive games that run remotely on cloud servers. This delivery paradigm is called Gaming as a Service (GaaS). GaaS is used to stream computer games across the Internet. It gives rise to various technical, legal, and ethi...

This paper describes a high-speed GaAs MESFET digital IC design for optical communication systems. We propose novel circuit configurations of a selector and a static delayed flip-flop which are key elements to perform high-speed digital functions. Employing these new design, the selector IC and static decision IC fabricated with 0.12-μm GaAs MESFET operated up to 44 Gbit/s and 22 Gbit/s, respec...

We report resonant Raman scattering (RRS) by the TO, LO, and 2 LO modes of single wurtzite and zincblende GaAs nanowires. The optical band gap of wurtzite GaAs is 1.460 eV± 3meV at room temperature, and 35± 3meV larger than the GaAs zinc-blende band gap. Raman measurements using incoming light polarized parallel and perpendicular to the wire c axis allowed us to investigate the splitting of hea...