Columbia University

Massachusetts Institute of Technology

Richard Osgood, Jr

Miguel Levy

Antonije M Radojevic

Daniel J Ehrlich

Chee Wei Wong

Xiaodong Yang

Thomas F Deutsch

James F McMillan

Jerry Dadap

Paul R Prucnal

Eric R Fossum

Alan E Willner

Tomoyuki Izuhara

Dragan V Podlesnik

Nicolae C Panoiu

Mark N Ruberto

Junichiro Fujita

Howard Schlossberg

David S Levy

Robert Scarmozzino

Nicolae Panoiu

Devices and methods for providing stimulated Raman lasing are provided. In some embodiments, devices include a photonic crystal that includes a layer of silicon having a lattice of holes and a linear defect that forms a waveguide configured to receive pump light and output Stokes light through Raman scattering, wherein the thickness of the layer of silicon, the spacing of the lattice of holes, and the size of the holes are dimensioned to provide Raman lasing. In some embodiments, methods include forming a layer of silicon, and etching the layer of silicon to form a lattice of holes with a linear defect that forms a waveguide configured to receive pump light and output Stokes light through Raman scattering, wherein the thickness of the layer of silicon, the spacing of the lattice of holes, and the size of the holes are dimensioned to provide Raman lasing.

Devices and methods for providing stimulated raman lasing

A method is provided for fabricating thin membrane structures in localized surface regions of a single crystal substrate. In the method, ion implantation masks are patterned on the surface of the single crystal substrate with openings that define the localized surface regions. Foreign ions are implanted through the openings into the single crystal substrate to modify the chemical and/or structural properties of subsurface layers at predetermined depths underneath super layers of material. These subsurface layers are removed by selective etching. The removal of the subsurface layers leaves the super layers of material intact as membrane structures on top of openings or channels corresponding to the space of the removed subsurface layers. At least one portion or end of a membrane structure remains attached to the single crystal substrate.

Methods for fabrication of localized membranes on single crystal substrate surfaces

A device and method for optical isolation for use in optical systems is disclosed. The device provides for a waveguide optical isolator fabricated using two arms, made of optical waveguides comprising magneto-optical material, in a Mach-Zehnder interferometer configuration. The device of the present invention operates using the TM mode of a light wave and, thus, does not require phase-matching of TM and TE modes. Further, the present invention does not use polarizers to extinguish the optical feed-back.

Waveguide mach-zehnder optical isolator utilizing transverse magneto-optical phase shift

The Multimode Interference coupler according to the invention has smoothly continuous inwardly tapered sidewalls ( ) which define the width of the multimode region (W ) along the propagation axis of the device. The inward taper causes the average width of the device to be reduced in comparison to known couplers having straight sidewalls ( ). Further, invention allows the access waveguides ( ) to remain sufficiently spaced, while reducing the overall length of the device, to avoid lithographic gap fill-in and unwanted optical coupling between the waveguides.

Reduced size multimode interference based coupler

A method for fabricating ultra-thin single-crystal metal oxide wave retarder plates, such as a zeroth-order X-cut single-crystal LiNbO half-wave plate, comprises ion implanting a bulk birefringent metal oxide crystal at normal incidence through a planar major surface thereof to form a damage layer at a predetermined distance d below the planar major surface, and detaching a single-crystal wave retarder plate from the bulk crystal by either chemically etching away the damage layer or by subjecting the bulk crystal having the damage layer to a rapid temperature increase to effect thermally induced snap-off detachment of the wave retarder plate. The detached wave retarder plate has a predetermined thickness d dependent on the ion implantation energy. A half-wave plate fabricated in accordance with this method may be used in conjunction with an optical waveguide section to form a TE-TM polarization mode converter by mounting the half-wave plate in a groove in the wageguide section perpendicular to the direction of wave propagation therein, bonding the half-wave plate to the back-end facet of the waveguide section or bonding the half-wave plate to the front-end facet of the waveguide section. In each case the normal mode axes of the half-wave plate is at 45&deg; with respect to the direction of the electric field vector of the TE or TM mode of propagation in the waveguide section.

Method for fabricating ultra thin single-crystal metal oxide wave retarder plates and waveguide polarization mode converter using the same

A method is provided for detaching a single-crystal film from an epilayer/substrate or bulk crystal structure. The method includes the steps of implanting ions into the crystal structure to form a damage layer within the crystal structure at an implantation depth below a top surface of the crystal structure, and chemically etching the damage layer to effect detachment the single-crystal film from the crystal structure. The thin film may be detached by subjecting the crystal structure with the ion implanted damage layer to a rapid temperature increase without chemical etching. The method of the present invention is especially useful for detaching single-crystal metal oxide films from metal oxide crystal structures. Methods for enhancing the crystal slicing etch-rate are also disclosed.

Slicing of single-crystal films using ion implantation

A method is provided for detaching a single-crystal film from an epilayer/substrate or bulk crystal structure. The method includes the steps of implanting ions into the crystal structure to form a damage layer within the crystal structure at an implantation depth below a top surface of the crystal structure, and chemically etching the damage layer to effect detachment the single-crystal film from the crystal structure. The method of the present invention is especially useful for detaching single-crystal metal oxide films from metal oxide crystal structures.

Crystal ion-slicing of single-crystal films

The sensitivity of localized photochemical etching to the optical and electrical properties of multilayered semiconductor materials is utilized for selectively etching a laterally extending undercut in a buried layer. The semiconductor body is immersed in a suitable etching solution and a beam of light of appropriate wavelength and intensity is directed onto the semiconductor solution interface. The buried layer has a longer diffusion length for photogenerated carriers than the layers adjacent thereto, casuing carriers to diffuse away from the illuminated region within the buried layer and thereby etch the buried layer laterally, undercutting the adjacent layers.

Method of localized photohemical etching of multilayered semiconductor

An integrated fiber optic coupler useful for the optical transmission of data from a light source to a detector located on a semiconductor chip which comprises a semiconductor wafer with a cavity etched into a surface, means wthin the cavity for converting light into an electrical signal, an electroconductive metal deposited on the surface of the semiconductor wafer around the opening of the cavity forming an electrical connection between the means for converting light into an electrical signal and circuitry etched into the wafer and an optical fiber inserted into the cavity and affixed to the semiconductor wafer.

Integrated fiber optic coupler for VHSIC/VLSI interconnects

A method of growing patterned films on a substrate in a deposition chamber without masking, the method consisting of the following steps: pressurizing the chamber with a fluid medium to form a thin absorption layer on the substrate; evacuating the chamber to remove excess fluid medium; prenucleating portions of the substrate with a focused energy beam; repressurizing the chamber with a fluid medium; and inducing deposition of material from the fluid medium and thereby growing a patterned film with deposition occuring primarily on the prenucleated portions of the substrate.

Growing community of inventors

Chappaqua, NY, United States of America

Richard Osgood, Jr