Quantum band engineering allows us to design materials with optical properties not readily found in nature. We pursue novel semiconductor nanostructures with potential applications in infrared light emission and detection. These materials employ optical transitions between energy levels brought about by quantum confinement in the conduction band of host semiconductors. Research on intersubband transitions has resulted in fundamental discoveries that eventually triggered practical device applications. I will describe our recent work to understand, model, and control the fundamental mechanisms of light absorption and electrical transport in nitride nanostructures. Special attention is given to the relationship between growth, structure, and optical properties in lattice-matched AlInN/GaN and nonpolar AlGaN/GaN superlattices. We found that infrared absorption in nitride superlattices is an extremely sensitive tool for the exploration of subtle and previously overlooked structural details of semiconductor nanomaterials. This insight has led to dramatically enhanced near-infrared absorption in lattice-matched AlInN/GaN superlattices, as well as the first demonstration of far-infrared absorption in m-plane nitride heterostructures. Current work is focused on the fundamental processes involved in the growth of novel nitride semiconductors. Using a combination of molecular-beam epitaxy, high resolution x-ray analysis, and transmission electron microscopy, we identified an unprecedented growth regime for m-plane AlGaN. Additional work seeks to unravel the early stage growth dynamics of the technologically important alloy Al0.83In0.17N.

Department of Physics General Colloquia

Researchers should cite this work as follows:

• Oana Malis (2018), "Novel III-Nitrides Materials for Infrared Optoelectronics: Growth, Structure and Properties," https://nanohub.org/resources/28945.

  BibTex | EndNote