Author's posts

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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As boas universidades no Brasil custam pouco, caro mesmo é não saber criar conhecimento

I would like to share out an interesting article (in Portuguese) thinking a bit about the cost and befits of the public founded universities of Brazil. It is worth reading “Excelência acadêmica requer custeio público“, an articled found at the webpages of Unicamp.    

After two years of refereeing: Nanoletter finally out

That must have been the longest submission in my scientific life.  After two years, with 14 referee reports from the first submission to Nature Photonics and three more rounds with Nanoletters our work: “Anisotropic Flow Control and Gate Modulation of Hybrid Phonon-Polaritons” is out. Light–matter interaction in two-dimensional photonic or phononic materials allows for the confinement …

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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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Conference right before 1st semester 2019

I will be at the EuroMBE 2019 in February taking the chance to see, what’s going on in the European (and International) community. The conference will be in the week before the 1st semester starts from February, 17th to 20th, 2019.  I will also present our work over membrane overgrowth in a poster session on …

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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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Membrane based solar cell paper

The membrane based solar paper in APL is out in which I was happy to contribute a bit: “Pixelated GaSb solar cells on silicon by membrane bonding” We demonstrate thin-film GaSb solar cells which are isolated from a GaSb substrate and transferred to a Si substrate. We epitaxially grow ∼3.3 μm thick GaSb P on N …

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Scientific publishing

A true comment from XKCD: Your manuscript “Don’t Pay $25 to Access Any of the Articles in this Journal: A Review of Preprint Repositories and Author Willingness to Email PDF Copies for Free” has also been rejected, but nice try. XKCD is published under Creative Commons Attribution-NonCommercial 2.5 License  at xkcd.org.

Do grades really serve the propose we want?

I read these days an interesting German article, questioning the future of grades as we give them today. Basically, he repeats a critic that we already discussed in our course in the EA2. The main points are: Grades are just a time snap of the moment. They do not tell you, what happened afterwards – …

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