RESEARCH
Surface and Interface Science:
Nanophotonics, Energy Science, Nonlinear Optics
Surface and Interface Science:
Nanophotonics, Energy Science, Nonlinear Optics
Keywords: Plasmonics and Nanophotonics, Metamaterials, Nanomaterials, Nanofabrication, Energy Harvesting, Sensors, Nonlinear Optical Spectroscopy, Scanning Probe Microscopy
Nanophotonics
Nanophotonics investigates the behavior of light on nanometer length scales and the interactions of light with nanometer-sized objects. Together with advances in nanofabrication and the development of new nanomaterials, manipulating light with structures that are smaller than its wavelength is spawning a revolution in optics, where the traditional methods of bending and manipulating light with lenses, mirrors and waveplates will be replaced by miniaturized “flat optics”, capable of controlling the amplitudes and phases of the electromagnetic fields through their interactions with the surface nanostructures. We have developed new materials chemistry that, when combined with state-of-the-art nanofabrication methods, produces large area arrays of oriented, single-crystal, noble metal nanostructures to form engineered “metamaterials” to tailor and manipulate light at the nanoscale.
Nanophotonics investigates the behavior of light on nanometer length scales and the interactions of light with nanometer-sized objects. Together with advances in nanofabrication and the development of new nanomaterials, manipulating light with structures that are smaller than its wavelength is spawning a revolution in optics, where the traditional methods of bending and manipulating light with lenses, mirrors and waveplates will be replaced by miniaturized “flat optics”, capable of controlling the amplitudes and phases of the electromagnetic fields through their interactions with the surface nanostructures. We have developed new materials chemistry that, when combined with state-of-the-art nanofabrication methods, produces large area arrays of oriented, single-crystal, noble metal nanostructures to form engineered “metamaterials” to tailor and manipulate light at the nanoscale.
Energy Science
As we transition from fossil fuel-based energy sources to clean and more environmentally friendly alternatives, there is a growing need for technologies that facilitate the storage of green, but intermittent, sources of electricity such as wind and solar. We are exploring new methods of energy harvesting, optical sensing, and chemical transformation through the excitation of the metallic free electrons (surface plasmons) that reside at the interface between nanotextured metals and their local environments to fill this need. The design of nanoantennas to capture, confine and amplify local electromagnetic fields can drive new physical and chemical phenomena in the vicinity of the nanostructures that can aid in energy harvesting and chemical catalysis. Surface plasmons decay into “hot” (energetic) charges that can be separated to generate electricity, provide an optical sensory response, and to catalyze the reduction of CO2 and water splitting to generate solar fuels and chemical feedstocks that will reduce our reliance on fossil fuels. We are exploring the factors that affect the yield of hot electrons, structures that provide short wave infrared (SWIR) response, and we are creating new alloy catalysts for the production of solar fuels.
As we transition from fossil fuel-based energy sources to clean and more environmentally friendly alternatives, there is a growing need for technologies that facilitate the storage of green, but intermittent, sources of electricity such as wind and solar. We are exploring new methods of energy harvesting, optical sensing, and chemical transformation through the excitation of the metallic free electrons (surface plasmons) that reside at the interface between nanotextured metals and their local environments to fill this need. The design of nanoantennas to capture, confine and amplify local electromagnetic fields can drive new physical and chemical phenomena in the vicinity of the nanostructures that can aid in energy harvesting and chemical catalysis. Surface plasmons decay into “hot” (energetic) charges that can be separated to generate electricity, provide an optical sensory response, and to catalyze the reduction of CO2 and water splitting to generate solar fuels and chemical feedstocks that will reduce our reliance on fossil fuels. We are exploring the factors that affect the yield of hot electrons, structures that provide short wave infrared (SWIR) response, and we are creating new alloy catalysts for the production of solar fuels.
Nonlinear Optics
We employ nonlinear optical spectroscopy as a tool to investigate the structure and dynamics of surface and interface environments. The inherent asymmetry of surfaces and surface forces often leads to the preferential ordering of interface species and a non-centrosymmetric local structure that provides interface selectivity through second (even)-order nonlinear optical response. We perform surface second harmonic generation (SHG) and vibrational sum frequency generation (VSFG) spectroscopy using short (fs/ps) optical pulses to provide a view of the energetics and ultrafast dynamics of molecular adsorbates in these important interfacial environments.
We employ nonlinear optical spectroscopy as a tool to investigate the structure and dynamics of surface and interface environments. The inherent asymmetry of surfaces and surface forces often leads to the preferential ordering of interface species and a non-centrosymmetric local structure that provides interface selectivity through second (even)-order nonlinear optical response. We perform surface second harmonic generation (SHG) and vibrational sum frequency generation (VSFG) spectroscopy using short (fs/ps) optical pulses to provide a view of the energetics and ultrafast dynamics of molecular adsorbates in these important interfacial environments.
We gratefully acknowledge funding support from the following organizations: