Quantum dots tuned to atomic resonances represent an emerging field of hybrid quantum systems where the advantages and natural atoms can be combined. Embedding in nanowires boosts these with a set powerful possibilities, such as precise positioning emitters, excellent photon extraction efficiency direct electrical contacting dots. Notably, nanowire structures grown on silicon substrates, allowing for straightforward integration silicon-based photonic devices. In this work we show controlled...

Based on the high-angle annular dark-field scanning transmission electron microscopy and energy dispersive X-ray spectroscopy studies, we unravel origin of spontaneous core–shell AlGaAs nanowires grown by gold-assisted molecular beam epitaxy. Our have a cylindrical core tapered shell. The composition shell is close to nominal, while aluminum content in systematically smaller than nominal. After switching off group III fluxes, droplet topmost part nanowire rapidly tends zero, gallium remains...

Harvesting hybrid mechanical and solar ambient energy with one small device remains a challenge. Here, we report on producing electric current using Schottky type metal-oxide-semiconductor structure formed by an n-InP layer covered native oxide atomic force microscope (AFM) probe conductive coating. The tip's sliding reciprocating motion during AFM scanning in contact mode produces direct signal the probe-sample circuit. Two power generation mechanisms exist. A strong was detected under...

Abstract InGaN nanostructures are among the most promising candidates for visible solid-state lighting and renewable energy sources. To date, there is still a lack of information about influence growth conditions on physical properties these nanostructures. Here, we extend study nanowires directly Si substrates by plasma-assisted molecular beam epitaxy. The results showed that under appropriate change in temperature just 10 °C leads to significant structural optical nanowires. with areas...

Fermi level pinning at the oxidized (110) surfaces of III-As nanowires (GaAs, InAs, InGaAs, AlGaAs) is studied. Using scanning gradient Kelvin probe microscopy, we show that cleavage ternary AlxGa1−xAs (0 ≤ x 0.45) and GaxIn1−xAs 1) alloys pinned same position 4.8 ± 0.1 eV with regard to vacuum level. The finding implies a unified mechanism for such surfaces. Further investigation, performed by Raman scattering photoluminescence spectroscopy, shows photooxidation leads accumulation an excess...

We demonstrate spontaneous core–shell In x Ga 1− N nanowires exhibiting bright photoluminescence at 650 nm. The surprising effect of material separation is attributed to the periodically changing environment for single monolayer growth.

Branched III-V nanowires are interesting both from the fundamental viewpoint and for development of electronic optoelectronic structures with enhanced functionality. Herein, we present a robust approach to synthesis branched AlGaAs using Au-catalyzed molecular-beam epitaxy directly on Si(111) substrates. The second third deposition Au onto substrate gives rise first generation branches. First branches grow in [1-100] direction perpendicular nanowire trunks; their coalescence yields bridging....

Generation of electric current is observed when GaAs nanowires with wurtzite crystal structure are bent by the probe an atomic force microscope. The originates from a piezo active phase in due to piezoelectric effect. Increasing piezo‐potential enhances tunneling through probe–nanowire Schottky barrier thermionic field emission. Laser illumination amplifies short‐circuit pulses two orders magnitude 9 pA 1 nA piezo‐phototronic Utilization such effect solution accelerate efficiency hybrid...

Abstract GaAs quantum dots in nanowires are one of the most promising candidates for scalable photonics. They have excellent optical properties, can be frequency-tuned to atomic transitions, and offer a robust platform fabrication multi-qubit devices that promise unlock full technological potential dots. Coherent resonant excitation is necessary virtually any practical application because it allows, instance, on-demand generation single entangled photons, photonic clusters states, electron...

Wurtzite AlGaAs is a technologically promising yet unexplored material. Here we study it both experimentally and numerically. We develop complete numerical model based on an 8-band k→·p→ method, including electromechanical fields, calculate the optoelectronic properties of wurtzite nanowires with different Al content. then compare them our experimental data. Our results strongly suggest that direct band gap Moreover, have also numerically obtained AlAs valence offset between GaAs in symmetry.

Hybrid nanostructures based on InGaN nanowires with decorated plasmonic silver nanoparticles are investigated in the present study. It is shown that induce redistribution of room temperature photoluminescence between short-wavelength and long-wavelength peaks nanowires. defined maxima decreased by 20%, whereas increased 19%. We attribute this phenomenon to energy transfer enhancement coalesced part NWs 10–13% In content tips above an about 20–23%. A proposed Fröhlich resonance model for NPs...

Abstract Semiconducting nanowires, unlike bulk, can be grown in both wurtzite and zincblende crystal phases. This unique feature allows for growth investigation of technologically important previously unexplored materials, such as AlGaAs . Here we grow a series nanowires with Al content varying from 0.1 to 0.6, on silicon substrates through comparative structural optical analysis experimentally derive, the first time, formula bandgap Moreover, bright emission short lifetime our suggest that...

Tailorable synthesis of axially heterostructured epitaxial nanowires (NWs) with a proper choice materials allows for the fabrication novel photonic devices, such as nanoemitter in resonant cavity. An example structure is GaP nanowire ternary GaPAs insertions form nano-sized discs studied this work. With use micro-photoluminescence technique and numerical calculations, we experimentally theoretically study photoluminescence emission individual NWs. Due to high refractive index near-zero...

The electronic properties of semiconductor AIIIBV nanowires (NWs) due to their high surface/volume ratio can be effectively controlled by NW strain and surface states. We study the effect applied tension on conductivity wurtzite InxGa1-xAs (x ∼ 0.8) NWs. Experimentally, conductive atomic force microscopy is used measure I-V curves vertically standing NWs covered native oxide. To apply tension, microscope probe touching side shifted laterally produce a tensile in NW. significantly increases...

GaN nanowires were grown using selective area plasma-assisted molecular beam epitaxy on SiOx/Si(111) substrates patterned with microsphere lithography. For the first time, temperature–Ga/N2 flux ratio map was established for of nanowires. It is shown that growth selectivity without any parasitic a silica mask can be obtained in relatively narrow range substrate temperatures and Ga/N2 ratios. A model developed explains range, which appeared to highly sensitive temperature Ga flux, as well...

Research regarding ways to increase solar cell efficiency is in high demand. Mechanical deformation of a nanowire (NW) can improve its efficiency. Here, the effect uniaxial compression on GaAs cells was studied via conductive atomic force microscopy (C-AFM) supported by numerical simulation. C-AFM I–V curves were measured for wurtzite p-GaAs NW grown p-Si substrate. Numerical simulations performed considering piezoresistance and piezoelectric effects. Solar reduction 50% under −0.5% strain...

We propose a new insight into the mechanism of low-temperature Au-assisted growth InAs nanowires. The nanowire MBE was achieved at temperature 270 °C on silicon substrates and described theoretically <italic>via</italic> vapor–solid–solid mechanism.