Journal ArticleDOI
Localized excitons in InAs self-assembled quantum dots embedded in InGaAs/GaAs multi-quantum wells
Tetyana Torchynska,J.L. Casas Espinola,Petr G. Eliseev,Andreas Stintz,Kevin J. Malloy,R. Peña Sierra +5 more
TLDR
In this article, the temperature-dependent photoluminescence spectra of highly uniform self-assembled InAs quantum dots (QDs) embedded in In 0.15 Ga 0.8 As/GaAs multi-quantum well (MQW) structures have been investigated.Abstract:
The temperature-dependent photoluminescence (PL) spectra of highly uniform self-assembled InAs quantum dots (QDs) embedded in In 0.15 Ga 0.8 As/GaAs multi-quantum well (MQW) structures have been investigated. Spectral peak shift and PL temperature quenching for ground state (GS) and first excited state (1ES) optical transitions in the range 12-220 K are analyzed. Small FWHM values equal to 37 and 27 meV at 12 K characterize the GS and 1ES transitions, respectively. For the highly uniform QDs no unusual decrease of the FWHM at low temperatures was seen that would be connected with the redistribution of carriers between the QDs. The activation energies of the PL temperature quenching processes for GS and 1ES in InAs QDs are found to be the same, about 50-52 meV. The reasons for the same GS and 1ES thermal activation energies in InAs self-assembled QDs are discussed.read more
Citations
More filters
Journal ArticleDOI
Ambient pressure photoelectron spectroscopy: A new tool for surface science and nanotechnology
Miquel Salmeron,Robert Schlögl +1 more
TL;DR: Ambient pressure photoelectron spectroscopy (APPES) as mentioned in this paper is a technique that can be used to analyze surfaces in the presence of gases and vapors, as encountered in industrial catalysis and atmospheric environments.
Journal ArticleDOI
Chemical control of the charge state of nitrogen-vacancy centers in diamond
Moritz V. Hauf,Bernhard Grotz,Boris Naydenov,Markus Dankerl,S. Pezzagna,Jan Meijer,Fedor Jelezko,Jörg Wrachtrup,Martin Stutzmann,Friedemann Reinhard,Jose A. Garrido +10 more
TL;DR: In this paper, the effect of surface termination on the charge state of nitrogen-vacancy (NV) centers, which have been ion-implanted a few nanometers below the surface of diamond, was investigated.
Journal ArticleDOI
Review on carbon-derived, solid-state, micro and nano sensors for electrochemical sensing applications
TL;DR: In this paper, the authors summarize the most relevant contributions in the development of electrochemical sensors based on carbon materials in the recent years and highlight the advantages of these carbon materials to promote different electron transfer reactions specially those related to biomolecules.
Journal ArticleDOI
X-ray absorption spectroscopic study of Fe reference compounds for the analysis of natural sediments
TL;DR: In this paper, a suite of 27 common, Fe-bearing reference compounds, including sulfides, carbonates, phosphates, oxides, oxyhydroxides, and phyllosilicates, was analyzed to empirically assess the utility of X-ray absorption near-edge structure (XANES) and extended Xray absorption fine structure (EXAFS) for identifying a particular Fe mineral (or class of minerals) in a soil or sediment mixture.
Journal ArticleDOI
Neutron imaging in materials science
TL;DR: An overview of the most important advances in the application of neutron imaging in materials research with a focus on novel techniques such as energy-selective imaging, interferometric imaging with phase gratings, and polarized-neutron imaging can be found in this article.