0000000000003118
AUTHOR
Jorge M. Garcia
Temperature dependent optical properties of stacked InGaAs/GaAs quantum rings
4 páginas, 3 figuras, 2 tablas.-- MADICA 2006 Conference, Fifth Maghreb-Europe Meeting on Materials and their Applicatons for Devices and Physical, Chemical and Biological Sensors
Optical Properties of Self-Assembled GaxIn1-xAs/InP Quantum Wires
Temperature dependent photoluminescence studies have been carried out on several samples containing self-assembled Ga x In 1-x As/InP quantum wires. A red-shift of the emission wavelength is observed when increasing the Ga content in the alloy, but the overall optical quality decreases. In the case of x = 0.15, the photoluminescence is not sensible to temperature and the emission band is conserved until room temperature is reached, which could be explained if the nanostructures are considered to be almost amorphous.
Influence of the InAs coverage on the phonon-assisted recombination in InAs/GaAs quantum dots
6 páginas, 3 figuras.
Size self-filtering effect in vertical stacks of InAs/InP self-assembled quantum wires
3 páginas, 2 figuras.-- PACS: 73.21.Hb; 78.55.Cr; 78.67.Lt.-- Proceedings of the International Conference on Superlattices, Nano-structures and Nano-devices ICSNN 2002.
Continuum and discrete excitation spectrum of single quantum rings
Photoluminescence and excitation of the photoluminescence spectroscopy has been performed in single InGaAs self-assembled quantum rings embedded in a field effect structure device. To determine their electronic structure, bias-dependent optical transitions have been analyzed both, for individual quantum rings, and for the averaged ensemble. Our results are compared with a theoretical model, and also with results reported by other authors studying similar nanostructures.
Competition between carrier recombination and tunneling in quantum dots and rings under the action of electric fields
6 páginas, 3 figuras.-- Proceedings of the 7th International Conference on Physics of Light-Matter Coupling in Nanostructures.
Size filtering effect in vertical stacks of In(Ga)As/GaAs self-assembled quantum rings
3 páginas, 3 figuras.
Isolated self-assembled InAs/InP(001) quantum wires obtained by controlling the growth front evolution
6 páginas, 5 figuras. In this work we explore the first stages of quantum wire (QWR) formation studying the evolution of the growth front for InAs coverages below the critical thickness, θc, determined by reflection high energy electron diffraction (RHEED). Our results obtained by in situ measurement of the accumulated stress evolution during InAs growth on InP(001) show that the relaxation process starts at a certain InAs coverage θRθR this ensemble of isolated nanostructures progressively evolves towards QWRs that cover the whole surface for θ = θc. These results allow for a better understanding of the self-assembling process of QWRs and enable the study of the individual properties of In…
Vertical stacks of small InAs/GaAs self-assembled dots: resonant and non-resonant excitation
4 páginas, 2 figuras.-- PACS: 78.67.Hc; 73.21.La; 78.55.Cr.-- Proceedings of the International Conference on Superlattices, Nano-structures and Nano-devices ICSNN 2002.
Oscillator strength reduction induced by external electric fields in self-assembled quantum dots and rings
We have carried out continuous wave and time resolved photoluminescence experiments in self-assembled In(Ga)As quantum dots and quantum rings embedded in field effect structure devices. In both kinds of nanostructures, we find a noticeable increase of the exciton radiative lifetime with the external voltage bias that must be attributed to the field-induced polarizability of the confined electron hole pair. The interplay between the exciton radiative recombination and the electronic carrier tunneling in the presence of a stationary electric field is therefore investigated and compared with a numerical calculation based on the effective mass approximation.
Carrier recombination in InAs/GaAs self-assembled quantum dots under resonant excitation conditions
5 páginas, 4 figuras.-- PACS: 73.21.La;73.63.Kv;78.55.Cr;78.67.Hc;S7.12.-- Trabajo presentado en la 7th International Conference on Optics and Excitons in Confined Systems (OECS7).
Effect of carrier transfer on the PL intensity in self-assembled In (Ga) As/GaAs quantum rings
We present results concerning the carrier transfer between In(Ga)As quantum rings in a stacked multilayer structure, which is characterised by a bimodal size distribution. This transfer of carriers explains the observed temperature behaviour of diode lasers based on that kind of stacked layer structures. The inter-ring carrier transfer can be possible by phonon assisted tunnelling from the ground state of the smallring family towards the big-ring family of the bimodal size distribution. This process is thermally activated in the range 40–80 K.
Optical transitions and excitonic recombination in InAs/InP self-assembled quantum wires
InAs self-assembled quantum wire structures have been grown on InP substrates and studied by means of photoluminescence and polarized-light absorption measurements. According to our calculations, the observed optical transitions in each sample are consistent with wires of different heights, namely from 6 to 13 monolayers. The nonradiative mechanism limiting the emission intensity at room temperature is related to thermal escape of carriers out of the wires.
Exciton recombination in self-assembled InAs/GaAs small quantum dots under an external electric field
5 páginas, 3 figuras.-- PACS: 73.63.Kv; 78.55.Cr; 78.67.Hc; S7.12.-- Trabajo presentado en la 7th International Conference on Optics and Excitons in Confined Systems (OECS7).