Guilherme Torelly

Pontifícia Universidade Católica do Rio de Janeiro · Department of Electrical Engineering (ELE)

Introduction The consensus among researchers is that early failure of dental implants is due to the lack of primary stability and compressive stress on the peri-implant bone that exceeds the physiological tolerance. Objective The objective of this work is to propose a new methodology to quantify bone stress during dental implant insertion and to c...

We review recent studies of cavity switching induced by the optical injection of free carriers in micropillar cavities containing quantum dots. Using the quantum dots as a broadband internal light source and a streak camera as detector, we track the resonance frequencies for a large set of modes with picosecond time resolution. We report a record-f...

We report on ultrafast all-optical switching experiments performed on pillar micro-cavities containing a collection of quantum dots (QDs). Using QDs as a broadband internal light source and a detection setup based on a streak camera, we track in parallel the frequencies of a large set (>10) of resonant modes of an isolated mi-cropillar, during the...

We report on the generation of few-ps long spontaneous emission pulses by quantum dots (QDs) in a switched optical microcavity. We use a pulsed optical injection of free charge carriers to induce a large frequency shift of the fundamental mode of a GaAs/AlAs micropillar. We track in real time by time-resolved photoluminescence its fundamental mode...

We report on the generation of few-ps long spontaneous emission pulses by quantum dots (QDs) in a switched optical microcavity. We use a pulsed optical injection of free charge carriers to induce a large frequency shift of the fundamental mode of a GaAs/AlAs micropillar. We track in real time by time-resolved photoluminescence its fundamental mode...

InAs QDs embedded in an AlGaAs matrix have been produced by MOVPE with a partial capping and annealing technique to achieve controllable QD energy levels that could be useful for solar cell applications. The resulted spool-shaped QDs are around 5 nm in height and have a log-normal diameter distribution, which is observed by TEM to range from 5 to 1...

An investigation of ultra-thin InAs layers deposited on GaAs is carried out combining theoretical calculations with results of high-resolution transmission electron microscopy, atomic force microscopy and photoluminescence. Five period InAs/GaAs epilayers were grown by metalorganic vapor phase epitaxy at a very low growth rate, with different InAs...

The formation of self-assembled InAs quantum dots is investigated as the growth time increases from 3.6 to 12 seconds at a low growth rate. The morphological evolution from a rough surface at a short length scale to an extended 2D InAs flat area, and finally to the 3D InAs islands is followed using atomic force microscopy, photoluminescence and tra...

Apresentamos técnicas de imageamento no infravermelho, que possibilitam ver no escuro e medir as temperaturas de um corpo ou de um ambiente. Alguns experimentos são propostos com o objetivo de auxiliar a visualização desse tipo de radiação, que está fora da faixa que conseguimos enxergar, e, por isso, dizemos invisível. O grande diferencial desses...