Principal Investigators: Todd H. Stievater and Marcel W. Pruessner, opticalmems@nrl.navy.mil

We are investigating the properties of micro/nano-opto-mechanical systems and subwavelength optical structures for next-generation photonics technologies. The high-index contrast and small feature sizes afforded by new precision patterning and etching technologies in semiconductors and low-loss dielectric materials enable the creation of new nanoscale optical devices. Optical interferometric techniques are emerging as simple, yet exquisitively sensitive methods to read-out MEMS sensors and actuators, while micromechanical and nanomechanical displacement is proving to be an ideal method to achieve large phase or amplitude changes for integrated optical systems. In addition, photonic structures that are wavelength-scale or smaller enable fascinating new properties, such as enormous form birefringence, huge evanescent fields, and geometry-dependent phonon-polaritonics.

We are taking advantage of these properties to develop revolutionary new photonics technologies, all based on optical characteristics that are impossible to achieve in macroscopic systems. Our fundamental investigations of topics such as nanoslot waveguiding, coupled opto-mechanical oscillation, and photothermal spectroscopy are investigated with an eye towards U.S. Navy applications in areas such as microwave photonics, chemical sensors, and free-space optical communication.

Specific areas of research include:

• Semiconductor electro-optics, nonlinear optics, and polaritonics: Suspended semiconductor waveguides are characterized by strong confinement with low loss and offer exciting new ways to take advantage of the nonlinear, electro-optic, and polaritonic properties of III-V materials.
• Evanescent-Field Absorption Spectroscopy: We are investigating highly evanescent silicon nitride and semiconductor waveguide microcavities for their ability to spectroscopically sense and characterize the local environment.
• Micromechanical Photothermal Spectroscopy: We are investigating optical interferometric and spectroscopic techniques to interrogate microbridges and microcantilevers that have been coated with functionalized materials.
• Silicon Photonics: Silicon waveguides form the basis of our research efforts in areas such as integrated components for microwave photonics, optical phased arrays, and much more.
• Cavity Optomechanics: Low-intensity light can exert a significant force on micro- and nano-mechanical structures.