Abstract: A semiconductor waveguide based optical receiver is disclosed. An apparatus according to aspects of the present invention includes an absorption region including a first type of semiconductor region proximate to a second type of semiconductor region. The first type of semiconductor is to absorb light in a first range of wavelengths and the second type of semiconductor to absorb light in a second range of wavelengths. A multiplication region is defined proximate to and separate from the absorption region. The multiplication region includes an intrinsic semiconductor region in which there is an electric field to multiply the electrons created in the absorption region.

Abstract: A tunable optical filter includes a tunable Fabry-Perot (FP) filter, two tunable waveguide Bragg gratings (WBGs) and a 2×2 3-dB coupler. In one embodiment, the WBGs are implemented in a silicon substrate using polysilicon filled trenches. The FP filter is implemented with two silicon nitride trench WBGs with a gap region between them. The FP filter and the WBGs are respectively tuned to transmit and reflect a selected wavelength. A broadband optical signal is propagated into a first port of the coupler. The coupler propagates half of the beam to one WBG and the other half to the other WBG. The WBGs reflect these portions back to the coupler, which then propagates the reflected portions to the FP filter.

Abstract: An avalanche photodetector is disclosed. An apparatus according to aspects of the present invention includes an absorption region including a first type of semiconductor. The first type of semiconductor material has a graded doping concentration of a dopant material within the absorption region. A multiplication region is proximate to and separate from the absorption region. The multiplication region includes a second type of semiconductor material in which there is an electric field. The electric field is to multiply the free charge carriers created in the absorption region. A reflector is disposed proximate to the multiplication region such that the multiplication region is between the absorption region and the reflector. The reflector is to reflect unabsorbed light that reaches the reflector from the absorption region back to the absorption region.

Abstract: A semiconductor waveguide based optical receiver is disclosed. An apparatus according to aspects of the present invention includes an absorption region including a first type of semiconductor region proximate to a second type of semiconductor region. The first type of semiconductor is to absorb light in a first range of wavelengths and the second type of semiconductor to absorb light in a second range of wavelengths. A multiplication region is defined proximate to and separate from the absorption region. The multiplication region includes an intrinsic semiconductor region in which there is an electric field to multiply the electrons created in the absorption region.

Abstract: An apparatus and method for high speed phase modulation of optical beam. For one embodiment, an apparatus includes an optical waveguide having adjoining first and second regions disposed in semiconductor material. The first and second regions have opposite doping types. A first buffer is disposed along the optical waveguide. A first higher doped region of semiconductor material is also included outside an optical path of the optical waveguide. An inner portion of the first higher doped region is adjoining and coupled to the first region of the optical waveguide. An outer portion of the first higher doped region is adjoining the first buffer. The first higher doped region has a higher doping concentration than a doping concentration within the optical path of the optical waveguide. A first contact having an inner portion adjoining and coupled to the first higher doped region is also included. The first contact has an outer portion adjoining the first buffer.

Abstract: A semiconductor waveguide based optical receiver is disclosed. An apparatus according to aspects of the present invention includes an absorption region including a first type of semiconductor region proximate to a second type of semiconductor region. The first type of semiconductor is to absorb light in a first range of wavelengths and the second type of semiconductor to absorb light in a second range of wavelengths. A multiplication region is defined proximate to and separate from the absorption region. The multiplication region includes an intrinsic semiconductor region in which there is an electric field to multiply the electrons created in the absorption region.

Abstract: An apparatus and method for modulating a phase of optical beam in an electrically isolated active region of an optical waveguide. In one embodiment, an apparatus according to embodiments of the present invention includes an active region of an optical waveguide disposed in a semiconductor layer. The active region includes a p doped region and an n doped region. The apparatus further includes an insulating region disposed in the semiconductor layer surrounding the active region in the semiconductor layer. The insulating region electrically isolates the active region of the optical waveguide from a passive region of the optical waveguide disposed in the semiconductor layer. An optical beam is to be directed through the optical waveguide and through the active region to be phase shifted in response to a modulated charge region in the active region in the optical waveguide.

Abstract: An apparatus and method for high speed phase modulation of optical beam with reduced optical loss. In one embodiment, an apparatus includes a first region of an optical waveguide disposed in semiconductor material. The first region has a first conductivity type. The apparatus also includes a second region of the optical waveguide disposed in the semiconductor material. The second region has a second conductivity type opposite to the first conductivity type. A first contact is included in the apparatus and is coupled to the optical waveguide at a first location in the first region outside an optical path of an optical beam to be directed through the optical waveguide. The apparatus also includes a first higher doped region included in the first region and coupled to the first contact at the first location to improve an electrical coupling between the first contact and the optical waveguide. The first higher doped region has a higher doping concentration than a doping concentration within the optical path.

Abstract: An apparatus and method for modulating a phase of optical beam independent of polarization. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide disposed in semiconductor material, the first region having a first conductivity type, and a second region of the optical waveguide disposed in the semiconductor material, the second region having a second conductivity type opposite to the first conductivity type. The apparatus also includes a substantially V shaped insulating region disposed between the first and second regions of the optical waveguide, wherein a vertex of the substantially V shaped insulating region forms an intersecting line that is substantially parallel to an optical path of an optical beam to be directed through the optical waveguide.

Abstract: An electrical-optical coupling and detecting device. An apparatus according to an embodiment of the present invention includes a reflective surface defined on semiconductor material. The reflective surface is to reflect an incident optical beam towards an optical destination. An optical detector is monolithically integrated in the reflective surface of the semiconductor material. The optical detector arranged in the reflective surface of the semiconductor material is to detect the incident optical beam.

Abstract: A tunable optical filter includes a tunable Fabry-Perot (FP) filter, two tunable waveguide Bragg gratings (WBGs) and a 2×2 3-dB coupler. In one embodiment, the WBGs are implemented in a silicon substrate using polysilicon filled trenches. The FP filter is implemented with two silicon nitride trench WBGs with a gap region between them. The FP filter and the WBGs are respectively tuned to transmit and reflect a selected wavelength. A broadband optical signal is propagated into a first port of the coupler. The coupler propagates half of the beam to one WBG and the other half to the other WBG. The WBGs reflect these portions back to the coupler, which then propagates the reflected portions to the FP filter.

Abstract: A tunable Bragg grating method and apparatus. In one aspect of the present invention, a method according to an embodiment of the present invention includes directing an optical beam into a first end of an optical path having the first end and a second end disposed in a semiconductor substrate, reflecting a first portion of the optical beam having a first center wavelength back out from the first end of the optical path and tuning the optical path to reflect a second portion of the optical beam having a second center wavelength back out from the first end of the optical path. In one embodiment, the Bragg grating is tuned with a heater used to adjust a temperature of the semiconductor substrate. In another embodiment, charge in charge modulated regions along the optical path is modulated to tune the Bragg grating.

Abstract: An optical device may include a fiber or waveguide that is intended to be coupled to another waveguide having a significantly larger/smaller cross-sectional size. As such, two wedge shaped waveguides may be positioned atop a tapered waveguide. The dual wedge design may allow for shorter taper lengths and smaller final waveguide cross section dimensions.

Abstract: A waveguide Bragg grating (WBG) is apodized by varying the duty cycle of selected grating periods while fixing the pitch of the grating periods. In one embodiment, the WBG is implemented in a silicon substrate using polysilicon filled trenches of varying width while keeping the grating periods' pitch constant. The polysilicon trenches are formed so that if the width of one trench is increased compared to an adjacent grating period, the trench width in the other adjacent grating period (if present) is decreased.

Abstract: An optical bistable silicon Raman laser is disclosed, which provides digital signal regeneration, reshaping and wavelength conversion. An apparatus according to aspects of the present invention includes an optical waveguide disposed in semiconductor material. First and second reflectors are disposed in the optical waveguide. The first and second reflectors define a cavity in the optical waveguide. The cavity is to receive a first optical beam having a first wavelength. A power level of the first optical beam received by the cavity rising above a second power level results in emission of a second optical beam of a second wavelength from the cavity until the power level of the first optical beam received by the cavity falls below a first power level. The first power level is less than the second power level.

Abstract: A fast optical modulator or switch with reduced optical loss is disclosed. An apparatus according to aspects of the present invention includes an optical splitter disposed in a semiconductor material. An optical beam having a first wavelength is split by the optical splitter into first and second portions. First and second optical waveguides disposed in the semiconductor material are optically coupled to the optical splitter. The first and second portions of the optical beam are to be directed through the first and second optical waveguides, respectively. The first optical waveguide is also optically coupled to receive a pump optical beam. The pump optical beam has a pump wavelength and a pump power level to amplify and phase shift the first portion of the optical beam of the first wavelength in the first optical waveguide.

Abstract: An optical device may include a fiber or waveguide that is intended to be coupled to another waveguide having a significantly larger/smaller cross-sectional size. As such, two wedge shaped waveguides may be positioned atop a tapered waveguide. The dual wedge design may allow for shorter taper lengths and smaller final waveguide cross section dimensions.

Abstract: An apparatus and method for modulating a phase of optical beam independent of polarization. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide disposed in semiconductor material, the first region having a first conductivity type, and a second region of the optical waveguide disposed in the semiconductor material, the second region having a second conductivity type opposite to the first conductivity type. The apparatus also includes a substantially V shaped insulating region disposed between the first and second regions of the optical waveguide, wherein a vertex of the substantially V shaped insulating region forms an intersecting line that is substantially parallel to an optical path of an optical beam to be directed through the optical waveguide.

Abstract: An apparatus and method for modulating a phase of optical beam independent of polarization. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide disposed in semiconductor material, the first region having a first conductivity type, and a second region of the optical waveguide disposed in the semiconductor material, the second region having a second conductivity type opposite to the first conductivity type. The apparatus also includes a substantially V shaped insulating region disposed between the first and second regions of the optical waveguide, wherein a vertex of the substantially V shaped insulating region forms an intersecting line that is substantially parallel to an optical path of an optical beam to be directed through the optical waveguide.

Abstract: A semiconductor based Raman laser and/or amplifier with reduced two-photon absorption generated carrier lifetimes. An apparatus according to embodiments of the present invention includes optical waveguide disposed in semiconductor material and a diode structure disposed in the optical waveguide. The optical waveguide is to be coupled to a pump laser to receive a first optical beam having a first wavelength and a first power level to result in emission of a second optical beam of a second wavelength in the semiconductor waveguide. The diode structure is to be biased to sweep out free carriers from the optical waveguide generated in response to two photon absorption in the optical waveguide.