Quantum Band Engineering with Nitride Semiconductors for Infrared Optoelectronics
Location:258 Fitzpatrick Hall
Quantum confinement in the conduction band of semiconductor heterostructures brings about fascinating optical properties in the infrared range of the spectrum. Research on intersubband transitions in recent years has resulted in fundamental discoveries that eventually triggered practical device applications. Our goal is to creatively exploit the unique properties of nano-structured III-nitride materials for novel light emitters and detectors in the currently under-developed near- and far-infrared ranges. Due to large electron effective mass, the nitride intersubband materials require the ability to fine-tune the atomic structure at an unprecedented sub-nanometer level. I will describe our efforts to understand, model, and control the effects of the nanostructure on optical properties and vertical transport in nitride heterostructures to realize the theoretical potential of this material system. Special attention will be given to the relationship between growth, structure, and optical properties in lattice-matched AlInN/GaN heterostructures. We also report the first observation of exactly reproducible low-temperature negative differential resistance in c-plane resonant tunneling diodes on low-defect quasi-bulk GaN substrates.
Prof. Oana Malis received a Ph.D. in Physics from Boston University. After a Postdoctoral appointment at Cornell University, she joined the semiconductor industry, first as a Product Development Engineer at IQE, Bethlehem, PA, and then as a research scientist at Bell Laboratories, Lucent Technologies. In 2006, Dr. Malis returned to academia, as an Assistant Professor of Physics at the State University of New York at Binghamton. Since 2009, she has been an Assistant Professor of Physics at Purdue University. Dr. Malis is interested in expanding the functionality of semiconductor optoelectronics in the infrared range of the spectrum using new materials and light emission processes. She is the recipient of an NSF Career Award and a Cottrell College Science Award from the Research Corporation for Science Advancement.