Publications associées à Towards polarization insensitive semiconductor optical amplifiers using InAs/GaAs columnar quantum dots

Physical insights from the aspect ratio dependence of turbulence in negative triangularity plasmas

In this work, we study the impact of aspect ratio A = R 0 / r (the ratio of major radius R 0 to minor radius r) on the confinement benefits of negative triangularity (NT) plasma shaping. We use high-fidelity flux tube gyrokinetic GENE simulations and consi ...

Iop Publishing Ltd2024

Fabrication and Characterization of High Aspect Ratio Amorphous Silicon Based Microchannel Plates

Christophe Ballif, Nicolas Würsch, Janina Christine Isabelle Löffler, Mohammad Beygi, Samira Alexandra Frey

This contribution focuses on the fabrication and characterization of microchannel plates made of hydrogenated amorphous silicon (AMCPs). Flexible fabrication processes and the semi-conducting nature of amorphous silicon could give these detectors the advan ...

2021

Tailored-Potential Semiconductor Quantum Nanostructures Grown in Inverted Pyramids

Mikhail Lazarev

We have focused on the ability to tune the aluminum (Al) content of the AlGaAs alloy along the growth direction in inverted pyramids (by MOVPE), thus tailoring the potential along a QWR nanostructure. Three parabolic-potential QDs (PQDs) of different poten ...

EPFL2019

Microfabrication of curved sidewall grooves using scanning nanosecond excimer laser ablation

Patrik Willi Hoffmann, André Gabriel Kostro, Josef Andreas Schuler, Georgios Violakis, Jing Gong

Novel glazing with embedded micro-mirrors can significantly reduce the energy consumption due to cooling and lighting in buildings. Especially promising are large arrays of periodic micro compound-parabolic-concentrators (CPCs) with angular-selected transm ...

SPIE2018

In-situ photopolymerization and monitoring device for controlled shaping of tissue fillers, replacements or implants

Dominique Pioletti, Andreas Schmocker, Azadeh Khoushabi, Christophe Moser

Photopolymerization is a common tool to harden materials initially in a liquid state. A surgeon can directly trigger the solidification of a dental implant or a bone or tissue filler simply by illumination. Traditionally, photopolymerization has been used ...

Spie-Int Soc Optical Engineering2015

Polarization Properties of Columnar Quantum Dots: Effects of Aspect Ratio and Compositional Contrast

Philipp Ridha

We report a systematic theoretical and experimental investigation of the polarization properties of columnar quantum dots (CQDs) with extremely large aspect ratio and high compositional contrast. A strong variation of the polarization of the dominant inter ...

2010

Polarization properties of semiconductor quantum dot and dash lasers

Philipp Ridha

Self-assembled quantum-dots (QDs) represent a distributed ensemble of zero dimensional structures, each presenting a near-singular density of states. The QD size, shape, areal density and optical properties depend on growth parameters, such as growth tempe ...

EPFL2008

Controlling the aspect ratio of quantum dots: From columnar dots to quantum dots

Marco Rossetti, Philipp Ridha

We demonstrate the feasibility and flexibility of artificial shape engineering of epitaxial semiconductor nanostructures. Novel nanostructures including InGaAs quantum rods (QRs), nanocandles, and quantum dots (QDs)-in-rods were realized on a GaAs substrat ...

2008

Optical polarization anisotropy and hole states in pyramidal quantum dots

Elyahou Kapon, Daniel Oberli, Alok Rudra, Valentina Troncale

The authors present a polarization-resolved photoluminescence study of single semiconductor quantum dots (QDs) interconnected to quantum wires, measured both in a top geometry, and in a less conventional cleaved-edge geometry. Strong polarization anisotrop ...

AIP American Institute of Physics2006