Trustees of the Colorado School of Mines

Other

Thomas E Furtak

Charles G Durfee

Reuben T Collins

Youngwoo Yi

This invention provides fundamental science and novel device architectures for surface plasmon (SP)-based, complementary metal oxide semiconductor (CMOS)-compatible, optical elements such as modulators, couplers, and switches. The primary focus of the work is on waveguides based on an ultra-long-range surface plasmon (ULRSP) waveguide mode recently discovered by our team. This mode exists at the metal-dielectric interfaces in a silicon-oxide-metal-silicon layer structure. While initial work focuses on noble metals to support the ULRSP, our analysis shows Si processing-compatible metals such as Cu and Al can also be used. Our modeling has also shown that variation in the thickness of the oxide layer can be used to give unprecedented propagation lengths in such structures. Electrically-induced free carrier modulation of the dielectric constant in the Si adjacent to the oxide can modulate the waveguide properties allowing novel Si-compatible electro-optic devices to be created. These waveguides function as the 'wiring' in new classes of optical chips. This invention also provides integration of ULRSP waveguides and switches with other optical elements to create entirely new classes of hybrid optoelectronic technologies for defense applications. These range from chip-based chemical agent detection to extremely high performance processors and even all-optical computations.

Silicon-compatible surface plasmon optical elements

The present invention provides a device that acts as an optical switch to control the intensity of a light beam through the action of a second control beam. This behavior is achieved through photoinduced anisotropy that develops in a monomolecular layer coating the inside surfaces of a liquid crystal cell. One of the surfaces is permanently aligned prior to assembly by illuminating the surface with polarized light in the presence of oxygen. The other surface retains reversible behavior, adapting anisotropy according to the orientation of the polarization of the control beam. Accordingly, an optically controlled liquid crystal light valve is provided that does not require contact-rubbing methods in order to permanently align one of the layers coating an inside surface of the cell.

All-optically prepared and controlled nematic liquid crystal light valve

The parallel detecting spectroscopic ellipsometer/polarimeter sensor has no moving parts and operates in real-time for in-situ monitoring of the thin film surface properties of a sample within a processing chamber. It includes a multi-spectral source of radiation for producing a collimated beam of radiation directed towards the surface of the sample through a polarizer. The thus polarized collimated beam of radiation impacts and is reflected from the surface of the sample, thereby changing its polarization state due to the intrinsic material properties of the sample. The light reflected from the sample is separated into four separate polarized filtered beams, each having individual spectral intensities. Data about said four individual spectral intensities is collected within the processing chamber, and is transmitted into one or more spectrometers. The data of all four individual spectral intensities is then analyzed using transformation algorithms, in real-time.

Growing community of inventors

Golden, CO, United States of America

Thomas E Furtak