CURRENT RESEARCH Femtosecond laser pulses provide the time resolution to measure ultrafast dynamics in physical and chemical systems, and the peak intensities to create extreme non-equilibrium conditions in matter. For research in science education, see the Education section. Optical hyperdoping: black silicon Silicon is doped to non-equilibrium levels by irradiating silicon with femtosecond laser pulses in a dopant rich environment. This novel material possesses unique optoelectronic properties. Femtosecond laser microfabrication Tightly focused femtosecond laser pulses in bulk dielectrics create nanometer-scale features with applications in data storage, optical communication, and laser surgery. Nanosurgery with femtosecond lasers Tightly focused femtosecond laser pulses provide a precise tool for imaging biological tissues and performing nanometer scale incisions within cells and living microorganisms. Surface-enhanced optical phenomena Metallic nanostructures are used to enhance localized optical fields for applications in spectroscopy, sensing, and nonlinear optics. Nonlinear Nanophotonics Nonlinear optical platforms where light can control light. ADDITIONAL RESEARCH AREAS We no longer carry out experiments in these areas, but you can still access the publications and other information we have on line. Ultrafast dynamics in solids Broadband measurements of the dielectric function with femtosecond time resolution provide new insights into electron and lattice dynamics. Femtosecond surface science Combining surface science techniques with femtosecond lasers provides a direct view of chemical reactions at surfaces. Optical studies of monolayers Structure and dynamics of monolayers at liquid surfaces. Silica nanowires Silica nanowires serve as rails for light in micro- and nanophotonics applications Spectroscopy of infrared multiphoton excited molecules Highly vibrationally excited molecules. Transport phenomena in dilute gases Transport of heat and matter in gases.

PLAINLY SPEAKING Our research involves the interaction of very short laser pulses (measured in "femtoseconds" or millionths of billionths of a second) with matter. On this time scale even the motion of light comes to a grinding halt: in one femtosecond light moves only a few thousandths of the diameter of a hair! The short duration of these laser pulses allows us to study phenomena that are inaccessible to any other means of detection. Eric Mazur in front of one of the group's femtosecond laser systems. Our work is of both fundamental interest and technological relevance, and crosses traditional disciplinary boundaries between physics, chemistry, materials science, and optics. We invite you to explore the areas describing our work, all of which are accompanied by non-technical explanations.