Category: Projects and Founding

New article: Band structure engineering in strain-free GaAs mesoscopic structures

We investigate the optical properties of strain-free mesoscopic GaAs/Al(x)Ga(1-x)As structures (MGS) coupled to thin GaAs/A(x)Ga(1-x)As quantum wells (QWs) with varying Al content (x). We demonstrate that quenching the QW emission by controlling the band crossover between AlGaAs X-point and GaAs Gamma-point gives rise to long carrier lifetimes and enhanced optical emission from the MGS. For …

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New article: Scanning Tunneling Measurements in Membrane-Based Nanostructures

Our new article: “Scanning Tunneling Measurements in Membrane-Based Nanostructures: Spatially- Resolved Quantum State Analysis in Postprocessed Epitaxial Systems for Optoelectronic Applications” is out in ACS Appl. Nano Mater. Nanoscale heterostructure engineering is the main target for the development of optoelectronic devices. In this sense, a precise knowledge of local electronic response after materials processing is …

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Article accepted in Nanoscale

In-place bonded semiconductor membranes as compliant substrates for IIIV compound devices Overcoming the critical thickness limit in pseudomorphic growth of lattice mismatched heterostructures is a fundamental challenge in heteroepitaxy. On-demand transfer of light-emitting structures to arbitrary host substrates is an important technological path for optoelectronics and photonics devices implementation.  The use of freestanding membranes as …

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Why the State of São Paulo is good in science and why it is important

The is a very nice article in Nature  discussing, why the state of SP is so good in science. Indeed, the state alone is responsible for more than 50% of Brazilian science production and  the leading place in South America. That this is of great importance for the country and the society is shown on …

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Back making rolled-up tubes

We are back to make rolled-up InGaAs/GaAs nano- and microtubes. We stopped doing the process for more than a year, but now is the time to strongly restart the activity. The light microscopy image shows one of our first process. The MBE grown sample coming from our machine rolls nicely, but we have to optimize …

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Universal 01/2016 – Faixa B

After long waiting, we got the acceptance news for our Proposal of last year submitted in the Universal 01/2016 – Faixa B. We hope to start the project soon as it will supports our research on overgrowth of membranes and rolled-up nanotubes. The project tile is: ” Nanoestruturas semicondutoras crescidas epitaxialmente sobre membranas para aplicações …

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