Intellectual Merits: In this project, the collective response of a dense cloud of confined charge is used as the basis for a number of high sensitivity detection applications including optical detectors, charged particle detectors, and the detectors of electromagnetic radiation in the terahertz frequency range. Optical detectors will be fabricated which circumvent the most limiting constraint on speed of device, the transit time of the carriers, by collecting them in a reservoir of charge and detecting the subsequent charge density waves. Charged-particle detectors will be designed, fabricated and analyzed which work on the same basis of the perturbation of such a reservoir. Coupling of electromagnetic radiation in the terahertz region and such devices will be studied and is expected to lead to the development of sensitive detectors of such radiation. These effects are enhanced with increase in the degree of confinement; as a result schemes for designing one-dimensional devices for photon and charged particle detection will be pursued. Successful completion of this project will have a broad scientific impact on the study of the collective response of electrons with application areas ranging from electron microscopy to optical communications, and biomedical engineering.
Broader impacts: The broader educational impact of this work will be magnified by building on a strong Drexel tradition of involving undergraduates in research at early stages of their education, and will leverage a number of NSF-sponsored programs including two Research Experiences for Undergraduates programs, including one specifically involving sensor development, a Research Experiences for Teachers site, an Integrative Graduate Education and Research program in nanotechnology and a GK-12 graduate fellowship and educational outreach program. Both undergraduates and graduates will be involved in growth, characterization, design, fabrication, and analysis of these nanostructured materials. In addition, much of the previous research leading to the present work is based on international collaboration and will be continued as a result of NSF support.
