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Tailoring Fundamental Light-Electron-Phonon Coupling through Nanoscale Materials Engineering Min Ouyang, University of Maryland College Park, DMR 0547194.
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Tailoring Fundamental Light-Electron-Phonon Coupling through Nanoscale Materials EngineeringMin Ouyang, University of Maryland College Park, DMR 0547194 In the FY11, we continued our former progresses in both materials control and ultrafast optical spectroscopy measurement at the nanoscale (see for examples, Science327, 1634-1638, 2010, and Nature466, 91-95, 2010), and we have achieved more sophistic fundamental control of a few physical process through nanoscale materials engineering. One example was shown in right figure. Figure A highlights an experimental scheme to impulsively launch fundamental electron and phonon interactions by incident ultrafast photon coupling process in a tunable core-shell nanostructures (unpublished). By combining this sophistic ultrafast optical measurement with our precise materials engineering of such as core-shell typed nanostructures with single atomic monolayer accuracy we have further demonstrated both fundamental electron-phonon coupling constant and acoustic phonon frequency can be tuned atomic layer by atomic layer (Figure B). These results have important implications in several fronts, and should open up the possibilities of fully control of quantum states and dynamic process at the nanoscale.
Tailoring Fundamental Light-Electron-Phonon Coupling through Nanoscale Materials EngineeringMin Ouyang, University of Maryland College Park, DMR 0547194 The FY11 was the third times that we have offered a new undergraduate course (entitled “Physics, Material Chemistry and Device Applications at the Nanoscale” (PHYS499M & ENMA 489X) and was cross-listed for different colleges). The PI has further polished course syllabus and course contents, including development of new experimental modulus. Left figure highlights a few course activities during Spring 2011 semester: Figure A exemplifies two student activities in lab: synthesizing nanoparticles in solution (left) and studying optical properties of nanowires (right). Figure B shows one lab result achieved by students by studying size dependent photo-luminscence of semiconductor CdSe quantum dots to gain insight of quantum confinement effect. Figure C highlights a new experiment involving manipulation of one-dimensional magnetic Ni nanowires by magnetic field under optical microscope to gain insight of anisotropic magnetism.