|Todd H. Stievater
We are investigating the scientific and technological properties of nanophotonic devices and nano-optomechanical systems. The high-index contrast, small feature sizes, and low loss afforded by new precision lithography in semiconductors and related materials enable the creation and study of entirely new types of nanophotonic optical devices. Our research ranges from fundamental scientific investigations to device development. Specific areas of interest include:
(1) Nonlinear Optics. We are investigating birefringent phase-matching in nanoslab III-V waveguides for efficient long-wave and mid-wave difference-frequency generation. We are also studying third-order optical nonlinearities in nanophotonic waveguides, such as Raman scattering and frequency comb generation.
(2) Cavity Optomechanics. We are investigating new materials and architectures for fully-integrated cavity opto-mechanics including novel cavities; innovative waveguide approaches (e.g. weak confinement, slot-modes, hybrid plasmonic, etc.); and novel sensors, oscillators, and modulators of interest to the Navy and DOD.
(3) Electro-Optics and Microwave Photonics. We are combining wafer-bonding and substrate removal techniques with state-of-the-art electro-optic materials and high-k dielectrics to investigate efficient, low-loss electro-optic modulation at ultra-high frequencies. We are also investigating integrated microwave photonics devices.
(4) Optical Sensing. We are making functionalized, highly evanescent waveguides in the near-IR, midwave-IR, and longwave-IR for spectroscopic detection of trace-gases, biological compounds, and other analytes of interest.
(5) Optical Phased-Arrays. We are investigating integrated photonics for all-optical phased arrays and nonmechanical beam steering, focusing on applications of interest for the DOD.
(6) Cold-Atom Nanophotonics. We are investigating nanophotonic waveguides for optical traps for cold atoms using the evanescent fields above the waveguides.
(7) Integrated Photonics and Nanophotonic Waveguides. We are investigating novel approaches and techniques to fabricate, use, and characterize subwavelength-scale waveguides.
Our work includes modeling and design, epitaxial growth, sample processing and device fabrication, and optical measurements and analysis. Research is conducted in collaboration with the Electronics Science and Technology Division, the Nanoscience Institute, and the Materials Science Division.
Waveguide; Nanophotonics; SOI; GaAs; InP; Nonlinear optics; Integrated photonics; DFG; Raman spectroscopy; Electro-optics; Wafer-bonding; Long-wave IR;
Mid-wave IR; Microwave photonics; Slot waveguide; Optical sensing; Optical phased-array;