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GaAs nanowires were heated locally under ambient air conditions by a focused laser beam which led to oxidation and formation of crystalline arsenic on the nanowire surface. Atomic force microscopy, photoluminescence and Raman spectroscopy experiments were ...
Thin-film InGaN photonic crystal (PhC) light-emitting diodes (LEDs) with a total semiconductor thickness of either 800 nm or 3.45 mu m were fabricated and characterized. Increased directional radiance relative to Lambertian emission was observed for both c ...
In the emerging field of soft robotics, there is an interest in developing new kinds of sensors whose characteristics do not affect the intrinsic compliance of soft robot components. Additionally, non-invasive shape and deflection sensors may provoke impro ...
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This work presents the experimental measurement of the extraction lengths of individual guided modes of embedded photonic-crystal (PhC) light-emitting diodes (LEDs), which corroborates its superior guided light extraction compared to surface PhC LEDs. Whil ...
The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are rela ...
We present the numerical optimization of GaN-based embedded 2D-Photonic Crystal (PhC) LEDs based on a full 3D scattering matrix model pointing out the importance of a proper vertical design in embedded PhC structures. The growth of such structures followin ...
The „Green Lighting“ project (LESO-PB/EPFL and Swiss Federal Office of Energy) explores different ways to combine advanced day- and artificial lighting technologies for achieving highly energy-efficient office lighting scenarios. This communication gives a ...
A theoretical approach based on coupled-mode theory is presented in order to determine the radiation pattern of LEDs incorporating a shallow photonic crystal. From this, a fundamental limit for the directionality of the diffraction of a single guided mode ...
Conductive zinc oxide (ZnO) grown by low pressure chemical vapor deposition (LPCVD) technique possesses a rough surface that induces an efficient light scattering in thin film silicon (TF Si) solar cells, which makes this TCO an ideal candidate for contact ...
The effect of surface passivation in BCl3/N-2 inductively coupled plasma reactive-ion etching of GaAs-based photonic crystals (PhCs) was investigated. It is shown that sidewall passivation is crucial for achieving cylindrical, vertical PhC holes, where the ...