Nanostructures

Nanostructures

N01–Nanowire antennas embedding single quantum dots: towards the emission of indistinguishable photons

Claudon J., Kotal S., Artioli A., Finazzer M., Fons R., Genuist Y., Bleuse J., Gérard J.-M., Wang Y., Osterkryger A. D., Gregersen N., Munsch M., Kuhlmann A. V., Cadeddu D., Poggio M., Warburton R. W., Verlot P.

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 […]

N02–Wave-function engineering in (In,Ga)As/(In,Al)As core/shell nanowires

Marquardt O., Geelhaar L., Brandt O.

 We study the electronic properties of In0.53Ga0.47As/InxAl1–xAs core/shell nanowires for light emission in the telecommunication range. In particular, we systematically investigate the influence of the In content x of the InxAl1–xAs shell and the diameter d of the In0.53Ga0.47As core on strain distribution, transition energies, and the character of the hole wave function. We show […]

N03–Numerical and Experimental Characterization of Chirped Quantum Dot-based Semiconductor Optical Amplifiers

Forrest A. F., Cataluna M. A., Krakowski M., Giannuzzi G., Bardella P.

We present a model for the description of the dynamical behavior of Quantum Dot (QD) based Semiconductor Optical Amplifiers (SOAs) under injection of optical pulses. The model uses a Time Domain Traveling Wave (TDTW) approach to describe the optical field in the amplifier, and allows us to consider chirped QD materials by the inclusion of […]

N04–Bismuth-containing GaAs core-shell nanowires

Usman Muhammad

This work theoretically investigates the electronic and optical properties of GaBixAs1–x/GaAs core–shell and GaAs/GaBixAs1–x/GaAs multi-core–shell nanowires. Our results show a large tuning of absorption wavelength (0.9 µ to 1.6 µ) by varying Bi composition and/or nanowire diameters. The computed polarisation dependent optical spectra indicate the possibility to incorporate such nanowires in photonic devices desiring isotropic […]

N05–Modeling the effects of p-modulation doping in InAs quantum dot devices

Maglio B., Jarvis L., Tang M., Liu H., Smowton P. M.

A modeling routine has been developed to quantify the effects of p-modulation doping in the waveguide core region of InAs quantum dot (QD) devices. Utilizing one dimensional approximations, simulated outputs of reverse and forward devices are simulated providing insight into absorption and gain properties.

N06–Optical properties of a waveguide-fed plasmonic nano-array through approximated scattering theory

Alam B., Ferraro A., d’Alessandro A., Caputo R., Asquini R.

We analyze the optical scattering properties of an array of Au nano-cylinders fabricated upon an ion-exchanged waveguide. The integrated systems is considered for fluoroscopy and Raman spectroscopy. Absorption, scattering and extinction have been calculated through a combination of Finite Difference Time Domain (FDTD) method and scattering theory. While a portion of the excitation signal interacts […]

N07–Short Pulses from QD Laser Excited State

Dogru N., Duranoglu Tunc S. H., Al-Dabbagh A. M.

 For the first time gain-switched short pulse generation with a width of 25-40 ps from excited state is demonstrated applying an external optical Gaussian beam to the excited state of InAs-InP-(113)B quantum dot laser.

N08–Dependence of conduction mechanism on bias and temperature in quantum-dot based electroluminescent devices

Rani S., Kumar J.

Quantum dots (QDs) provide some unique properties which make them preferable over other luminescent materials, one such property being adjustable and sharp emission which makes it an interesting candidate for electroluminescent devices. A QD based electroluminescent device has been taken into consideration in this theoretical study. The effect of the bias, temperature, the presence of […]

N09–Luminescence Decay Kinetics of Electron-Hole Plasma in II-VI Epitaxial Layers and Micropowders

Urmanov B. D., Leanenya M. S., Yablonskii G. P.

The luminescence decay kinetics of epitaxial layers of ZnSe and micropowders of ZnSe and CdS were measured at room temperature and at high levels of optical excitation. Comparison of the experimental results with the theoretically calculated decay kinetics showed good agreement for the initial moment of time at high concentrations of nonequilibrium charge carriers.