SAND 2011-4993W

Research Challenge 6: Beyond Spontaneous Emission Reflectivity data from a GaN microcavity showing anti-crossing behavior and strong coupling. This Research Challenge explores radiative processes that go beyond incoherent emission. For example, although light-emitting diodes (based on spontaneously-emitted incoherent light) are presently thought of as the source of choice for white light generation. However, coherent light [...]

 Research Challenge 5: Enhanced Spontaneous Emission (a) Core/shell nanoparticle geometry: (b) A cross section of the optical intensity distribution around the core/shell nanoparticle. (c,d) Internal optical intensity enhancement as a function of core radius and thickness when the size-dependent values of the metal’s dielectric functions are used. c) Au, d) Ag shells. Our explorations focus [...]

Research Challenge 4: Defect-Carrier Interactions Measured density of an InGaN QW deep level defect located 0.15 eV above the valence band edge. Note that the density is much higher in the rightmost QW1 closest to the n-type GaN region. This Research Challenge aims to develop an in-depth understanding of the electrical, optical and structural properties [...]

Research Challenge 1: Nanowires Composite CL image of InGaN/GaN core-shell nanowire luminescence. This Research Challenge explores the synthesis and properties of GaN/InGaN nanowires as a materials architecture for visible light-emission. If nanowire devices could span the entire visible spectrum, the RYG-gap  would be overcome. In addition, such full-spectrum emission would enable chromaticity-tunable light, which could [...]

Research Challenge 3: Competing Radiative and Non-Radiative Processes Conduction and valence band profile of an InGaN MQW LED active region including GaN barrier modification due to polarization fields and Si doping. Dominant emission is from the rightmost (p-side) QW. This Research Challenge aims to develop a microscopic understanding of the competing physical processes that determine [...]