Nanowires are promising solids for creating efficient optoelectronic and nanophotonic devices. Here, we study the optical properties of single InP/InAsP/InP nanowire transferred to Ag/SiOx plasmonic substrate. For the first time, photoluminescence enhancement for these nanowires due to exciton-plasmon interaction was demonstrated.

The effect of cooling conditions in the plasma-assisted molecular-beam epitaxy growth on the structural and optical properties of InGaN nanostructures is studied. It is shown that cooling of the samples without nitrogen plasma contributes to the suppression of phase separation in InGaN nanostructures. The integrated intensity of photoluminescence from these nanostructures increased by a factor of 2.

InGaAs quantum dots in AlGaAs nanowires were formed using molecular-beam epitaxy on the silicon surface for the first time. The dependence of the synthesized nanostructures physical properties on growth conditions was studied. The results of optical properties studies showed that photoluminescence spectra from InGaAs quantum dots are observed at room temperature in a wide range of wavelengths from 850 to 1300 nm. Based on experimental data, modeling of the optical properties of the synthesized nanostructures was carried out.

In this work, we studied the influence of the III/V flux ratio on the structural and optical properties of InGaN nanowires grown by plasma-assisted molecular beam epitaxy. It was found that the formation of InGaN nanowires with a core–shell structure occurs if the III/V flux ratio is about 0.9–1.2 taking into account the In incorporation coefficient. At the same time, an increase in the III/V flux ratio from the intermediate growth regime to metal-rich one leads to a decrease in the In content in nanowires from ~45% to ~35%. This nanowires exhibit photoluminescence at room temperature with a maximum in the range of 600–650 nm. A further increase in the III/V flux ratio to ~1.3, or its decrease to ~0.4 leads to the formation of coalesced nanocolumnar layers with a low In content. The results obtained may be of interest for studying the growth processes of InGaN nanowires and creating RGB light-emitting devices on them.

In this study, for the first time, the influence of the III/V flux ratio on the structural and optical characteristics of InGaN nanowires grown by plasma-assisted molecular beam epitaxy are investigated. It is found that the formation of InGaN nanowires with a core–shell structure occurs when the III/V flux ratio (taking into account the In-incorporation coefficient) is about 0.9–1.2. At the same time, an increase in the III/V flux ratio from the intermediate growth conditions to metal-rich conditions leads to a decrease in the In content in nanowires from 45 to 35

It has been revealed that removing the shell of spontaneously formed InGaN nanowires increases the amplitude and narrows their emission spectrum. It has been established that radiative recombination dominates in the nanowires. And the dependence of the integrated photoluminescence intensity on the pump power for nanowires after etching is superlinear in comparison with the initial ones.

We study the influence of the shell in InGaN nanowires with spontaneously formed core-shell structure on their optical and morphological properties. It is shown that removing the shell from the initial nanowires induces the photoluminescence enhancement and changes their spectrum emission. Our research shows that etching the shell of these nanowires nanocrystals leads to their deviation from the vertical position.

Experimental results of studying the InAs islands formation of silicon surface by molecular beam epitaxy are presented. It has been found that, InAs islands with both bimodal and uniform size distributions can be formed depending on the Si surface relief and the presence of nanopits. The possibility of fabricating heterostructures with InAs quantum dots demonstrating photoluminescence in the region of 1.65 μm, was showed.

Nanostructures based on III-N materials are promising candidates for ultraviolet and visible light emitting devices. In particular, ternary InGaN nanowires (NWs) grown on semiconductor wafers perfectly fit to optoelectronic applications. In this paper, we will show that InGaN/Si NWs system is quite sensitive to the growth conditions and even a small change in the growth temperature leads to a significant change in morphological properties of the NWs and also shifts the photoluminescence spectra from blue to red regions with In content in the NWs increase. We will also demonstrate that, under specific growth temperatures, InGaN NWs may be grown in a form of core-shell structure where indium composition in the core is much higher than In content in the core one.

A model of spontaneous formation of the core-shell structure in (In,Ga)As nanowire grown via molecular beam epitaxy without independent radial growth is proposed. Within the framework of the proposed model, the distribution of In across the axis of the nanowire was fitted. Keywords: core-shell nanowire, ternary nanowire, InGaAs nanowire, radial nanowire heterostructure.

The features of photoluminescence (PL) of hybrid nanostructures based on InP/InAsP/InP nanowires array with deposited colloidal CdSe/ZnS-trioctylphosphine oxide quantum dots at increasing pump power have been studied. Pumping was carried out by 10 ps laser pulses duration with 1 MHz repetition rate at 532 nm wavelength in the quasi-resonant region of QDs absorption. It has been established, that PL maximum of the nanostructure shifts hypsochromically with increasing of laser power, revealing a gradual dominance of the bands of its components. This PL manifestation is explained by the cascade filling of excited excitonic states, accompanied by the Auger recombination processes and light quenching. The role of free carriers absorption and energy exchange between excitonic states at high pump intensities is noted, as well as a sharp PL duration reduction associated with an increase of stimulated processes in absorption.

For n-type doping of A3B5 semiconductors silicon are commonly used. However, Si in A3B5 nanowire is p-type dopant. Species are incorporated into nanowire through the intermediate liquid phase. Solubility of metals in catalyst are usually much more than nitrogen family elements. Nitrogen family elements easily dissolve in metal carbon family elements such as lead and tin. Here we discuss the growth of GaAs nanowires with lead catalyst on Si substrate. Lead could easily dissolve nitrogen family elements as well as boron family elements, which allows to switch nanowire growth from metal-rich to pnictide-rich growth.

We present the results of experimental studies on the synthesis by molecular-beam epitaxy of AlGaAs nanowires with InAs quantum dots. The morphological, structural, and optical properties of the grown nanostructures have been studied. It is important to note that the emission from quantum dots is observed in the wavelength range from 750 to 970 nm. Assumptions about the nature of short-wavelength emission from quantum dots are formulated. In particular, one of the reasons may be a significant desorption of indium atoms and the presence of gallium atoms in catalyst drops during the growth at a substrate temperature of 510◦C. The proposed technology opens up new possibilities for integration direct-gap III−V materials with a silicon platform for various applications in photonics and quantum communications.

In this work, the photoluminescence of single InGaN NWs with a core-shell structure is investigated along their entire length at RT and 77 K. Multicolor emission, covering the spectral range from 380 to 650 nm, was obtained and described in details. Using the modified Vegard's law, the photoluminescence lines were correlated with the InGaN composition. Based on these results, conclusions about the structural properties and homogeneity of the InGaN NWs along their length were carried out.

The effect of cooling conditions in the plasma-assisted molecular-beam epitaxy growth on the structural and optical properties of InGaN nanostructures is studied. It is shown that cooling of the samples without nitrogen plasma contributes to the suppression of phase separation in InGaN nanostructures. The integrated intensity of photoluminescence from these nanostructures increased by a factor of 2.

In this work, we propose a simple method to enhance the photoluminescence of InGaN nanowires using CdSe/ZnS colloidal quantum dots. It is found that decoration the surface of InGaN NWs with QDs leads to an increase in the integral and peak photoluminescence intensity by more than 3 times. The observed enhancement is attributed to the nonradiative energy transfer between quantum dots and nanowires.

AlGaAs nanowires with InAs quantum dots on the silicon surface were synthesized by molecular-beam epitaxy. Morphological and optical properties of grown nanostructures were studied. It is important to note, that emission from quantum dots is observed in the wavelength range from 780 to 970 nm. Assumptions about the nature of short-wave radiation from quan-tum dots were formulated. In particular, one of the reasons may be the significant desorption of indium atoms and the presence of gallium atoms in the catalyst droplets during growth at the substrate temperature of 510 degrees C. Our work, therefore, opens new prospects for integration of direct bandgap semiconductors with silicon platform.

Experimental results of studying the InAs islands formation of silicon surface by molecular beam epitaxy are presented. It has been found that, InAs islands with both bimodal and uniform size distributions can be formed depending on the Si surface relief and the presence of nanopits. The possibility of fabricating heterostructures with InAs quantum dots demonstrating photoluminescence in the region of 1.65 μm, was showed.

An approach to the fabrication of LED structure based on GaN nanowires with thick core-shell InGaN insertions with high indium content is studied. The results of optical measurements demonstrate the photoluminescence from the InGaN insertions in the green spectrum at room temperature. The study of electrical properties shows typical diode dependence. The results can be crucial for the development of light-emitting diodes on Si substrates.

Germanium nanocrystals were grown on GaN nanowire sidewalls by molecular beam epitaxy. The transmission electron microscopy measurements revealed the formation of 6-10 nm in size Ge quantum dots, which exhibited diamond cubic crystal structure. Raman spectroscopy indicate that uncapped Ge QDs are stress relaxed compared to ones additionally capped with GaN.