Our research has three main focus areas, organized around the common theme of measuring and manipulating the properties of nanometer-scale objects:

1) Single-Molecule Microscopy & Spectroscopy:
Development of a novel technique, energy-filtered STM, to image individual molecules adsorbed at solid surfaces with chemical specificity. Development of state-of-the-art instrumentation for microscopy and spectroscopy on single molecules.
(Image (top): Si(111) 7x7 imaged with cleaved InAs probe. Semiconductor probes are being developed specifically for highest resolution spectro-microscopy on single molecules)
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2) Epitaxial Integration of Strained Nanostructures on Ultrathin Composite Substrates:
Exploration of the potential of epitaxial nanostructures as tools for inducing elastic strain, band structure changes, and material redistribution in ultrathin silicon-on-insulator (SOI). Pathways to nanoscale band structure engineering and spontaneous processing of semiconductor materials.
(Image (center): Estimated band structure changes induced in ultrathin SOI by a {105} faceted Ge 'stressor')
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3) Synthesis of Nanostructured Materials:
Fundamental mechanisms of epitaxial growth, studied by low-energy electron microscopy (LEEM) and in-situ scanning tunneling microscopy (STM). Organization mechanisms of self-assembled quantum dot islands. Initial stages of the growth of polycrystalline thin films.
(Image (bottom): faceted Ge quantum dot island, formed by stress-driven self-assembly on a Si(100) substrate)
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