The fabrication of strain-free mesoscopic GaAs structures (MGS) by Ga-assisted droplet etching (see sketch below) has attracted attention of the scientific community due to the excellent optical emission characteristics with sharp emission lines associated to different excitonic states. One way to expand the MGS application perspectives is to explore band structure engineering. In this sense, …
Heat generation on larger circuit boards is well-understood; however, at the nanoscale, the relationship between heat and electricity remains unanswered due to lack of appropriate thermometers capable of thermal monitoring without perturbing the system. Unfortunately, temperature measurement at the submicrometer spatial range is not possible with conventional contact thermometers. A way to overcome this impasse …
In collaboration with Prof. Christoph Deneke, we studied the optical emission of molecular beam epitaxy grown semiconductor systems on free and flexible membranes. We obtain optically active nanostructures (quantum wells) regrown on released GaAs/InGaAs/GaAs membranes used as virtual substrates. Together with our demonstrated ability to transfer thin semiconductor membranes before overgrowth to a new host …
In collaboration with the Federal University of São Carlos, the University of Brasília, the University of Southampton, and the University of Nottingham, we investigated the properties of charged excitons in large-area WS2, a transition metal dichalcogenide. We investigate in details the recombination dynamics of the different excitonic complexes of the system. We show that, in …
Carrier recombination processes are demonstrated to be tuned by tunneling effects in a quantum well coupled to a quantum dot ensemble. Carrier density is demonstrated to affect recombination rates in a dramatic way. The understanding of the experimental results is performed by an examination of the bimolecular recombination dynamics of the system. To get the …
Semiconductor nanowires have been extensively investigated in the last few years due to their new physical properties and enormous perspectives for applications. In this work, we investigate the effects of GaAsP passivation on strained GaAs core-shell nanowires. We demonstrate that, as a result of the decrease of the density of surface states, 4 orders of …
Surface acoustic waves (SAWs) have were employed to demonstrate high frequency (750MHz) single-photon sources (SPS). By remotely pumping electrons and holes into a GaAs quantum well, we were able to transport and inject them into quantum dots which work as efficient SPS. Our achievements represent a novel approach in the direction of high speed quantum …
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