Seminar 10/16/2013 - Oana Malis, Purdue University: Quantum Band Engineering in III-Nitride Semiconductors
Abstract: Quantum confinement in the conduction band of semiconductor heterostructures brings about fascinating optical properties in the infrared range of the spectrum due to intersubband transitions. Research on intersubband transitions in recent years has resulted in fundamental discoveries that eventually triggered practical device applications. In this talk I will focus on our efforts 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 work to understand, model, and control the fundamental underpinnings of light generation and electrical transport in nitride nanostructures. Special attention will be given to the relationship between growth, structure, and optical properties in lattice-matched nitride heterostructures. We also report the first observation of exactly reproducible low-temperature negative differential resistance in c-plane nitride resonant tunneling diodes. These results lay the groundwork for future technological breakthroughs.
Bio: Prof. Malis received a M.S. Degree in Physics from the University of Bucharest, Romania, and a Ph.D. in Physics from Boston University in 1999. After a Post-Doctoral position at Cornell University, Dr. Malis took a position in industry at IQE, Inc., Bethlehem, PA, to perform research on dilute nitride telecommunication lasers. In 2003 Dr. Malis joined the Quantum Cascade Laser research group at Bell Labs, Lucent Technologies. Dr. Malis continued her research on quantum cascade lasers after leaving Bell Labs in 2006, first as an Assistant Professor in the Physics Dept. at Binghamton University, and since 2009 as an Assistant Professor in the Physics Dept. at Purdue University. She is the recipient of a Career Award from the National Science Foundation and a Cottrell College Science Award from the Research Foundation for Science Advancement. Prof. Malis current research interests include optical and structural properties of semiconductor nanostructures for infrared optoelectronics and metallic nanoparticles for catalysis.
All seminars are held on Wednesdays from 12:00 noon-1:00 p.m. in the Bowen Hall Auditorium Room 222. A light lunch is provided at 11:30 a.m. in the Bowen Hall Atrium immediately prior to the seminar.
Location: Bowen Hall Auditorium
Date/Time: 10/16/13 at 12:00 pm - 10/16/13 at 1:00 pm
Category: PRISM/PCCM Seminar Series