Massachusetts Institute of Technology

Intel Corporation

Kazumi Wada

Lionel Cooper Kimerling

Desmond Rodney Lim

Jurgen Michel

Kevin Kidoo Lee

Shoji Akiyama

Anuradha Murthy Agarwal

Hermann A Haus

Jun-Fei Zheng

Franz Xaver Kaertner

Christina Manolatou

Donghwan Ahn

Douglas D Cannon

Juejun Hu

Tian Gu

Jifeng Liu

Daniel Knight Sparacin

Derek Kita

Junying Li

Fleur Jacolien Fok

Eveline Postelnicu

Samarth Aggarwal

Michelle L Clark

Yasuhiko Ishikawa

Felix Jan Grawert

Steven G Johnson

Ivan Celanovic

Paul A Maki

Victor Trinh Nguyen

Drew Michael Weninger

Jan-Malte Fischer

Noriaki Toyoda

Milov Popovic

Lionel C Kimmerling

Francis O'Sullivan

Natalija Z Jovanovic

Samuel Serna

A layer of amorphous Ge is formed on a substrate using electron-beam evaporation. The evaporation is performed at room temperature. The layer of amorphous Ge has a thickness of at least 50 nm and a purity of at least 90% Ge. The substrate is complementary metal-oxide-semiconductor (CMOS) compatible and is transparent at Long-Wave Infrared (LWIR) wavelengths. The layer of amorphous Ge can be used as a waveguide in chemical sensing and data communication applications. The amorphous Ge waveguide has a transmission loss in the LWIR of 11 dB/cm or less at 8 &#x3bc;m.

Amorphous germanium waveguides for spectroscopic sensing and data communication applications

Optical interconnects can offer higher bandwidth, lower power, lower cost, and higher latency than electrical interconnects alone. The optical interconnect system enables both optical and electrical interconnection, leverages existing fabrication processes to facilitate package-level integration, and delivers high alignment tolerance and low coupling losses. The optical interconnect system provides connections between a photonics integrated chip (PIC) and a chip carrier and between the chip carrier and external circuitry. The system provides a single flip chip interconnection between external circuitry and a chip carrier using a ball grid array (BGA) infrastructure. The system uses graded index (GRIN) lenses and cross-taper waveguide couplers to optically couple components, delivers coupling losses of less than 0.5 dB with an alignment tolerance of &#xb1;1 &#x3bc;m, and accommodates a 2.5&#xd7; higher bandwidth density.

Simultaneous electrical and optical connections for flip chip assembly

An apparatus for generating a spectral image includes a filter to receive incident light. The filter has a variable refractive index. The apparatus also includes a modulator, operably coupled to the filter, to modulate the variable refractive index of the filter so as to generate a plurality of optical patterns from the incident light. The plurality of optical patterns represents the spectral image and each optical pattern in the plurality of optical patterns corresponds to a different modulation of the variable refractive index. The apparatus further includes a detector, in optical communication with the filter, to detect the plurality of optical patterns.

Methods and apparatus for spectral imaging

An optical semiconductor includes a first semiconductor layer and at least one reflective element that is formed on the semiconductor layer. The at least one reflective element comprises alternating layers of high and low index layers. A crystalline semiconductor layer is formed on the at least one reflective element.

Optical device comprising crystalline semiconductor layer and reflective element

An on-chip amplifier includes first element that curtails the velocity of an incoming light to the amplifier. A second element is doped so as to make the frequency of the incoming light equal to the electron frequency in order to allow for electron-photon wave interaction, so that when current flows through the amplifier, electron power is transferred to the incoming light, resulting in amplification of the incoming light.

On-chip optical amplifier

A phototransistor includes an emitter and a base that comprises Ge. A collector comprises Si. The base, emitter, and collector form at least one Si/Ge heterojunction allowing the unpinning of Fermi energy level (E) of the phototransistor.

Ge photodetectors

An optical grating is disposed on a waveguide to redirect light from the interior of the waveguide through the opposite side of the waveguide from the grating. In one embodiment the waveguide, the grating, and an optical sensor are combined in a single monolithic structure. In another embodiment, an absorbing layer is directly connected to the waveguide in the region of the grating. In still another embodiment, efficiency of the grating is improved by having a high index contrast between the refractive index of the grating and the refractive index of the cladding disposed over the grating, and by having an appropriately sized discontinuity in the grating.

Optical grating coupler

An optical cavity structure for bending optical signals is provided. The optical cavity structure includes an input port for receiving input optical signals from a first waveguide. The optical cavity structure also includes an interconnecting structure that receives said input optical signals and interconnects said first waveguide to a second waveguide, the interconnecting structure further includes at least four straight edges that orthogonal and of a finite width. The optical cavity structure further includes an output port coupled to the interconnecting structure for providing the second waveguide with the input optical signals. Further, the optical cavity structure may be used to create three dimensional splitter devices and resonators.

Three dimensional high index optical waveguides bends and splitters

An optical device includes at least two photonic bandgap crystal (PBG) stacks that are each comprised of alternating layers of high and low index materials. A defect region is formed in a cavity region between the at least two photonic bandgap crystal stacks so as to provide the properties needed to reflect light received by the optical device.

Photonic bandgap modulator, amplifier, demux, and TDM devices

Light transmission is maximized through the pass band of a photonic bandgap (PBG) crystal (having alternating high- and low-index material) while preserving high reflection for stop band. An anti-reflective coating (ARC) is used to coat the PBG crystal wherein the ARC material has a refractive index of n=(n&#xd7;n)and thickness around &#x3bb;c/8 where &#x3bb;c is center wavelength.

Anti-reflection coating for the pass-band of photonic bandgap crystal

An optical modulator includes at least one waveguide medium that receives light. An absorption medium absorbs the light under predefined conditions and outputs optically modulated light. The absorption medium is comprised of a Ge-based structure. The Ge-based structure uses the Franz-Keldysh effect to create said optically modulated light.

Light modulation using the Franz-Keldysh effect

An optical device is provided. The optical device includes a plurality of high index layers. The optical device also includes a plurality of low index layers. The optical device is formed by creating alternating layers of the plurality of high layers and the plurality of low index layers, such that electricity and heat is allowed to be conducted through said optical device.

Thermally and electrically conducting high index contrast multi-layer mirrors and devices

An optical reflector includes an optical reflective element that comprises alternating layers of high and low index layers. A new substrate is bonded on the optical reflective element. The sequence of layers in the reflective element is reversed in order such that the layers grown first with lowest surface roughness are exposed to the highest electric field strength, and the layer grown last, of highest roughness, are buried deep in the multilayer stack.

Process for fabrication of high reflectors by reversal of layer sequence and application thereof

Growing community of inventors

Lexington, MA, United States of America

Kazumi Wada