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Combinations of III–V nanowires (NWs) with quantum dots (QDs) are promising building blocks for quantum light sources. Herein, for the first time, the results of growing AlGaAs NWs with InGaAs QDs by molecular‐beam epitaxy on a silicon substrate are shown. The optimal growth temperature is determined and the physical properties of the grown nanostructures are studied. It is shown that the grown nanostructures exhibit photoluminescence (PL) signal up to room temperature in a wide wavelength range, including 1.3 μm emission which is important for the optical fiber transmission. It is found that in addition to InGaAs QDs radial InGaAs quantum wells are formed inside the NWs as a result of lateral/axial InGaAs growth competition. The proposed technology opens up new possibilities for the integration of direct‐band III–V materials with the silicon platform for various applications in the field of silicon photonics and quantum communication technology. [ABSTRACT FROM AUTHOR]

Experimental data on the rapid (≈4.4 nm s−1) axial growth rate of narrow (≈9 nm in radius) InAs nanowires (NWs) obtained by Au‐catalyzed molecular beam epitaxy on Si substrates at a low surface temperature of 270 °C are presented. These NWs exhibit pure wurtzite crystal structure and an unusually high ratio of the average NW length over the effective thickness of deposited InAs of about 60 despite the presence of parasitic InAs islands on the Si substrate. These trends are explained within a dedicated growth model. In the absence of In evaporation, In atoms either diffuse from the substrate to the NW tips or remain in the parasitic layer. This leads to a linear time dependence of the NW length and other unusual growth properties that are thought to have not previously been accessed. [ABSTRACT FROM AUTHOR]

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

The piezoelectric effect in wurtzite-type GaAs nanowires was theoretically analyzed using an electromechanical 3D model. The difference between the theoretical and measured piezoelectric strain coefficient is explained by an enhanced pressing force of the contact layer on the nanowire. Simulations show the potential decreasing when nanowires are partly inside in the top metal contact due to a decreasing effective length and pressing force enhancement. [ABSTRACT FROM AUTHOR]

The anomalous piezoelectric effect in GaAs nanowires was detected (the piezoelectric strain coefficient up to d33 ≈ 26 pC/N) that is 12 times larger than the theoretically estimated value. This result is explained by the dominant content of the phase with the wurtzite-type crystal structure in GaAs nanowires and an increased pressing force by the contact layer on the nanowire. (© 2016 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Growth and properties of the self‐catalyzed heterostructured GaP nanowires (NWs) with GaP1 − xAsx insertions in the form of nanodiscs (NDs) grown by means of molecular‐beam epitaxy on Si (111) substrate are studied. To obtain the NDs with the different composition and optoelectronic properties, the ratio of As and P fluxes is varied. Structural properties of the synthesized heterostructures are characterized by means of transmission electron microscopy. Energy dispersive X‐ray spectroscopy is used to study chemical composition of the NDs. The maximum achieved fraction x in the NDs is nearly 60%. Sublinear dependence of As concentration in the ND on the As/P flux ratio is observed and theoretical description for the observed phenomenon is provided. The proposed model can be used to estimate the predicted As/P ratio for the synthesis of GaPAs NDs as well as NWs of the required composition. Microphotoluminescence (μPL) studies demonstrate the appearance of broadband PL signal in the spectral range between 600 and 700 nm, corresponding to the NDs with different compositions. Spectra intensity modulation is found due to longitudinal Fabry–Pérot‐type resonances in the individual NWs. [ABSTRACT FROM AUTHOR]