0000000000084203
AUTHOR
Luisa González
Different regimes of electronic coupling and their influence on exciton recombination in vertically stacked InAs/InP quantum wires
8 páginas, 8 figuras.
Growth of low-density vertical quantum dot molecules with control in energy emission
This article is distributed under the terms of the Creative Commons Attribution Noncommercial License.-- This article is part of the series 8th International Workshop on Epitaxial Semiconductors on Patterned Substrates and Novel Index Surfaces.
Consequences of the spatial localization on the exciton recombination dynamics in InGaP/GaAs heterostructures
5 páginas, 4 figuras.
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.
Different strategies towards the deterministic coupling of a single Quantum Dot to a photonic crystal cavity mode
In this work we show two different procedures of fabrication aiming towards the systematic positioning of single InAs quantum dots (QDs) coupled to a GaAs photonic crystal (PC) microcavity. The two approaches are based on the molecular beam epitaxial (MBE) growth of site-controlled QDs (SCQDs) on pre-patterned structures. The PC microcavity (PCM) is introduced previous or after the growth, on each case. We demonstrate the InAs SCQD nucleation on pre-patterned PCMs and a method to perform the QD nucleation respect to an etched ruler that is used to position the PC structure after growth. For both types of structures, we have carried out microphotoluminescence (µPL) spectroscopy experiments a…
Initial stages of self-assembled InAs/InP(001) quantum wire formation
4 páginas, 2 figuras.-- PACS codes: 78.67.Lt; 68.65.La; 68.37.Ps.-- Comunicación oral presentada a la 14ª International Conference on Molecular Beam Epitaxy - MBE XIV celebrada en Tokio (Japón) del 3 al 8 de Septiembre de 2006.
Charge control in laterally coupled double quantum dots
4 figuras, 4 páginas.-- PACS number(s): 78.67.Hc, 73.21.La, 78.55.Cr
Exciton kinetics and luminescence in disordered InxGa 1-xP/GaAs quantum wells
Trabajo presentado en el 7th International Workshop on Nonlinear Optics and Excitation Kinetics in Semiconductors, NOEKS 2003, celebrado en Karlsruhe (Alemania), del 23 al 28 de febrero de 2003
Exciton and multiexciton optical properties of single InAs/GaAs site-controlled quantum dots
We have studied the optical properties of InAs site-controlled quantum dots (SCQDs) grown on pre-patterned GaAs substrates. Since InAs nucleates preferentially on the lithography motifs, the location of the resulting QDs is determined by the pattern, which is fabricated by local oxidation nanolithography. Optical characterization has been performed on such SCQDs to study the fundamental and excited states. At the ground state different exciton complex transitions of about 500 μeV linewidth have been identified and the fine structure splitting of the neutral exciton has been determined (≈65 μeV). The observed electronic structure covers the demands of future quantum information technologies.…
Influence of the InAs coverage on the phonon-assisted recombination in InAs/GaAs quantum dots
6 páginas, 3 figuras.
Single Photon Emission from Site-Controlled InAs Quantum Dots Grown on GaAs(001) Patterned Substrates
5 páginas, 5 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.
Excitation power dependence of the Purcell effect in photonic crystal microcavity lasers with quantum wires
The Purcell effect dependence on the excitation power is studied in photonic crystal microcavity lasers embedding InAs/InP quantum wires. In the case of non-lasing modes, the Purcell effect has low dependence on the optical pumping, attributable to an exciton dynamics combining free and localized excitons. In the case of lasing modes, the influence of the stimulated emission makes ambiguous the determination of the Purcell factor. We have found that this ambiguity can be avoided by measuring the dependence of the decay time on the excitation power. These results provide insights in the determination of the Purcell factor in microcavity lasers. © 2013 AIP Publishing LLC.
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.
Correlation between optical properties and barrier composition in InxGa1−xP/GaAs quantum wells
9 páginas, 11 figuras.
Morphological evolution of InAs/InP quantum wires through aberration-corrected scanning transmission electron microscopy
Evolution of the size, shape and composition of self-assembled InAs/InP quantum wires through the Stranski–Krastanov transition has been determined by aberration-corrected Z-contrast imaging. High resolution compositional maps of the wires in the initial, intermediate and final formation stages are presented. (001) is the main facet at their very initial stage of formation, which is gradually reduced in favour of {114} or {118}, ending with the formation of mature quantum wires with {114} facets. Significant changes in wire dimensions are measured when varying slightly the amount of InAs deposited. These results are used as input parameters to build three-dimensional models that allow calcu…
Raman scattering and infrared reflectivity in [(InP)5(In0.49Ga0.51As)8]30 superlattices
6 páginas, 6 figuras, 1 tabla.
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…
Pressure dependence of optical phonons in ZnCdSe alloys
5 páginas, 2 figuras, 2 tablas.-- PACS 62.50.+p, 63.20.Dj, 78.30.Fs, 78.66.Hf.-- et al.
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.
Raman study of self-assembled InAs/InP quantum wire stacks with varying spacer thickness
http://link.aip.org/link/?JAPIAU/104/033523/1
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.
Temperature dependence of the effective mobility edge and recombination dynamics of free and localized excitons in InGaP/GaAs quantum wells
3 páginas, 1 figura.-- Comunicación presentada al Proceedings of the International Conference on Superlattices, Nano-structures and Nano-devices ICSNN 2002 o-structures and Nano-devices ICSNN 2002.
Exciton Gas Compression and Metallic Condensation in a Single Semiconductor Quantum Wire
4 páginas, 5 figuras.-- PACS numbers: 78.67.Lt, 71.30.+h, 71.35. -y.-- Comunicación presentada a la International Conference on the Physics of Semiconductors (ICPS) celebrada en Rio de Jqaneiro (Brasil/2008).
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).
Raman spectroscopy and photoluminescence of ZnTe thin films grown on GaAs
5 páginas, 4 figuras, 1 tabla.
Exciton recombination dynamics inInAs∕InPself-assembled quantum wires
In this work we investigate the exciton recombination dynamics in InAs/ InP semiconductor self-assembled quantum wires, by means of continuous wave and time resolved photoluminescence. The continuous wave photoluminescence results seem to indicate that the temperature quenching of the emission band seems to be more probably due to unipolar thermal escape of electrons towards the InP barrier. On the other hand, the analysis of time resolved photoluminescence reveals that the temperature dependence of the radiative and nonradiative recombination times is mainly determined by the dynamics of excitons localized by disorder shigh energy tail of the PL bandd and strongly localized slow energy tai…
Electrical control of a laterally ordered InAs/InP quantum dash array
5 páginas, 5 figuras.
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.
Emission properties of single InAs/GaAs quantum dot pairs and molecules grown in GaAs nanoholes
Trabajo presentado a la "11th International Conference on Optics of Excitons in Confined Systems" (OECS), celebrada en en Madrid (España) del 7 al 11 de Septiembre de 2009.
Pressure dependence of photoluminescence of InAs/InP self-assembled quantum wires
6 páginas, 4 figuras, 1 tabla.-- PACS 62.50.+ p, 73.21.Hb, 78.55.Cr, 78.67.Lt, 81.15.Hi, 81.16.Dn
Size and emission wavelength control of InAs/InP quantum wires
5 páginas, 5 figuras, 1 tabla.-- Comunicación presentada al E-MRS 2004 Spring Meeting celebrado en Estrasburgo (Francia) Mayo del 2004.
Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange
The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.
Band Alignments in InxGa1–xP/GaAs Heterostructures Investigated by Pressure Experiments
6 páginas, 3 figuras.
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).