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A quantum dot is a semiconductor nanostructure that confines the motion of conduction band electrons and valence band holes in all three spatial directions, thus creating fully discrete energy levels. The confinement in the InAs/GaAs material system is gen ...
We combine photonic crystal and quantum cascade band engineering to create an in-plane laser at terahertz frequency. We demonstrate that such photonic crystal lasers strongly improve the performances of terahertz quantum cascade material in terms of thresh ...
The field of photonic crystals is a rapidly developing branch of modern optics. Photonic crystals are believed to be the cornerstone for a wide range of new photonic devices controlling the confinement and propagation of light. These artificial structures ...
We demonstrated lasing from a high quality-factor photonic crystal surface mode, which brings several advantages for easy fabrication and efficient coupling. Temporal measurements indicate nearly ring-down time limited response. (C) 2007 Optical Society of ...
Efficiency and speed of photonic crystal lasers are improved by passivating InGaAs/GaAs membranes using (NH(4))S treatment. Lasers show five-fold reduction in nonradiative surface recombination rate, resulting in four-fold reduction in threshold and room-t ...
In this letter, we take advantage of the high coefficient of thermal expansion (CTE) of a chemically amplified, epoxy-based negative polymer (SU-8) to define a low-power consumption polymeric variable optical attenuator that combines the working principles ...
The authors report on InGaN microcavity light-emitting diodes with an effective thickness of similar to 450 nm at the emission wavelength of similar to 415 nm. The starting material for the flip-chip laser lift-off device is a structure with an active regi ...
This work addresses feature size effects (the lag-effect and roughness development) in chemically assisted ion beam etching (CAIBE) etching of InP-based photonic crystals. Photonic crystal fields with varying hole size and periods were etched with differen ...
International Society for Optical Engineering, Bellingham WA, WA 98227-0010, United States2006
With the aim of increasing the efficiency of green and blue light-emitting diodes, we investigate the luminescence of InGaN/GaN quantum wells on structured GaN buffer layers. ...
Gallium Nitride (GaN) and its ternary alloys with aluminium and indium have met a growing interest in the last decade. These semiconductors have a large direct bandgap and can be doped with either silicon (Si) for n-type and magnesium (Mg) for p-type layer ...
