Polarity determination in ZnSe nanowires by HAADF STEM

High angle annular dark field scanning transmission electron microscopy is used to analyze the polarity of ZnSe nanowires grown, by molecular beam epitaxy, on GaAs substrates. The experimental results are compared to simulated images in order to verify possible experimental artefacts. In this work we show that for this type of nano-objects, a residual tilt of the specimen below 15 mrad, away from the crystallographic zone axis does not impair the interpretation of the experimental images

Insertion of CdSe quantumdots in ZnSe nanowires : MBE growth and microstructure analysis

ZnSe nanowire growth has been successfully achieved on ZnSe (100) and (111)B buffer layers deposited on GaAs substrates. Cubic [100] oriented ZnSe nanowires or [0001] oriented hexagonal NWs are obtained on (100) substrates while [111] oriented cubic mixed with [0001] oriented hexagonal regions are obtained on (111)B substrates. Most of the NWs are perpendicular to the surface in the last case. CdSe quantum dots were successfully incorporated in the ZnSe NWs as demonstrated by transmission electron microscopy, energy filtered TEM and high angle annular dark field scanning TEM measurements

Control of the incubation time in the vapor-solid-solid growth of semiconductor nanowires

International audienceNanowires grown in the vapor-solid-solid mode using solid gold nanoparticles as a catalyst may exhibit a strong fluctuation of their length mostly due to the presence of an incubation time with a large distribution. We show that this is efficiently cured by an appropriate preparation of the catalyst nanoparticle-in the case of ZnTe nanowires by adding a Zn flux during the dewetting process. While NWs start at any time after dewetting in vacuum (resulting in a broad length distribution, up to a factor of 10), the incubation time is quite uniform after dewetting under Zn exposure. Residual fluctuations (reduced to below a factor of 2) are due to fluctuations of the nanoparticle size and to a change of the nanoparticle morphology during the growth

Diffusion-driven growth of nanowires by low-temperature molecular beam epitaxy

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Epitaxial growth of ZnSe and ZnSe/CdSe nanowires on ZnSe

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Correction to Ultrafast Room Temperature Single-Photon Source from Nanowire-Quantum Dots

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Nanowire antennas embedding single quantum dots: towards the emission of indistinguishable photons

Nanowire antennas embedding a single semiconductor quantum dot (QD) represent an appealing solid-state platform for photonic quantum technologies. We present recent work aiming at generating indistinguishable photons with this system. We first investigate decoherence channels that spectrally broaden the QD emission, and discuss in particular the impact of nanowire thermal vibrations. We also develop nanowire optical nanocavities, which provide a large acceleration of the QD spontaneous emission, so that it becomes less sensitive to environmental noises