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Thin, single semi conducting layer of GaInN, possibly containing a small percentage of arsenic, phosphorus or antimony, the said layer emitting at least two visible lights with determined colours which can be combined, particularly to obtain white light. M ...
This paper describes recent work on high-occupancy effects in semiconductor microcavities, with emphasis on the variety of new physics and the potential for applications that has been demonstrated recently. It is shown that the ability to manipulate both e ...
Institute of Electrical and Electronics Engineers2002
A blue resonant cavity light emitting diode with a 50% Al-content crack-free GaN/AlGaN distributed Bragg reflector is reported. The structure shows excellent optical properties and the benefits of the cavity structure are clearly seen in the narrowed spect ...
We have found experimentally that the exciton oscillator strength decreases dramatically with increase of the QW width in a GaN/Al0.07Ga0.93N system. The collapse of the oscillator strength is a manifestation of the polarisation field effect, as confirmed ...
Measurements of spontaneous emission from InGaAsP semiconductor optical amplifiers provide information on both the carrier density and temperature. By spatially resolving the light emitted along the active layer of the device, we find evidence of longitudi ...
Light emitting diodes (LEDs) based on In(x)Gal(1-x)N (x = 0.15-0.2)/GaN multiple-quantum wells ( MQWs) have been grown on sapphire substrates. Their wavelength emission can be tuned from blue to orange by increasing the QW thickness. This opens the way for ...
Resonant-cavity InGaN/GaN quantum well light emitting diodes have been fabricated. Nitride layers were grown by molecular beam epitaxy on Si (111). We fabricated the structures using a combination of Si substrate etching, GaN etching and dielectric (Ta2O5/ ...
We present a study on the dependence of the external Quantum Efficiency (QE) of Light Emitting Diodes (LEDs) on the device properties and p-contact metallisation. The external QE could be doubled by changing the p-type contact from oxidised Ni/Au to non-an ...
By comparing photoluminescence and photo reflectance spectra taken on a series of InGaN-GaN quantum wells grown under identical conditions except the growth time of the InGaN layers, we could monitor the Quantum Confined Stark Effect (QCSE) without changin ...
The use of photonic crystals (PCs) for realistic light emitting diodes (LEDs) is discussed, given the constraints of planar semiconductor technology. A viable route for the fabrication of high-efficiency high-brightness electrically injected LEDs is presen ...
