Watt Webb, professor in Applied and Engineering Physics and director of Cornell’s Developmental Resource for Biophysical Imaging Opto-electronics, in collaboration with others, invented a microchip with light-impeding holes for observing single molecules in their natural, enzymatic, functional state.

The microchip’s holes—two million 40-nanometer holes in the aluminum toplayer of a 25-millimeter-square chip—serve as waveguides for a 488-nanometer laser. (The light-impeding holes have a diameter one-tenth the wavelength of light.) The holes impede and reflect light so that a tiny amount of residual light can be used to optically isolate individual biomolecules with their naturally occurring substrate concentrations and measure their dynamic behavior during chemical reactions.

The new instrument represents a major step in the ability to isolate a single, active biomolecule for study, and it can be extended to other biological systems, such as a new method of DNA sequencing by which a genetic code can be “read” from a single DNA molecule. It also promises to aid in future drug discovery because it provides a powerful new way of looking at fluctuations in behavior of individual enzyme molecules.

Professor John Silcox in Applied and Engineering Physics continues to exploit an atomic-size electron beam coupled with electron spectroscopy to determine electronic-structural features on the atomic scale.

His latest electron scattering instrument is based on aberration correctors for electron lenses and is expected to achieve 1Å probe size and 0.3 eV energy resolution. This instrument improves on a previous best spatial resolution of 2Å that was achieved at Cornell in 1989.

Atomic-precision maps of electron scattering enable researchers to observe such phenomena as growth in thin-films, bonding at the interface of metals and ceramics, and the strain and atomic distributions in quantum wells and wires.