Abstract: Certain examples present an improved compressed-air energy storage system. The system can include multiple sequential stages, in which accumulators are charged with air, which influences a hydraulic fluid to influence a pump/motor, and vice versa.

Abstract: Certain examples present an improved compressed-air energy storage system. The system can include multiple sequential stages, in which accumulators are charged with air, which influences a hydraulic fluid to influence a pump/motor, and vice versa.

Abstract: Semiconductor structures having at least one quantum well heterostructure grown strain-free on Si(100) via a Sn1-xGex buffer layer and their uses are provided.

Abstract: A semiconductor structure including a single quantum well Ge1?x1?ySix1Sn/Ge1?x2Six2 heterostructure grown strain-free on Si(100) via a Sn1?xGex buffer layer is shown.

Abstract: Apparatus and methods for switching N optical input signals to M optical outputs are disclosed. In an example, an apparatus includes a plurality of optically transparent fabrics. Each of the fabrics receive at least one optical input signal and switch that received signal to at least one of a plurality of intermediate outputs. A multiplexer is operatively coupled between the intermediate outputs of the plurality of optically transparent fabrics and the M optical outputs.

Abstract: A temperature sensing and control method and apparatus. In one aspect of the present invention, an apparatus according to the teachings of the present invention includes an optical path disposed in semiconductor material. A four-terminal resistor is defined in the semiconductor material. At least a portion of the optical path is directed through the four-terminal resistor. The four-terminal resistor includes a first pair of terminals between which a probe current is to be injected. The four-terminal resistor also includes a second pair of terminals between which a voltage drop is to be measured so as to determine a resistance along the portion of the optical path directed through the four-terminal resistor. Temperature may be derived from the determined resistance of the four-terminal resistor. In one embodiment, the temperature of the semiconductor material may then be controlled with a heater in response to the derived temperature.

Abstract: A doped barrier region included in an optical phase shifter is disclosed. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide and a second region of the optical waveguide. The second region of the optical waveguide includes a higher doped region of material and a lower doped region of material. An insulating region disposed between the first and second regions of the optical waveguide is also included. A first portion the higher doped region is disposed proximate to the insulating region. A dopant barrier region is also included and is disposed between the higher and lower doped regions of the second region of the optical waveguide.

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: A doped barrier region included in an optical phase shifter is disclosed. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide and a second region of the optical waveguide. The second region of the optical waveguide includes a higher doped region of material and a lower doped region of material. An insulating region disposed between the first and second regions of the optical waveguide is also included. A first portion the higher doped region is disposed proximate to the insulating region. A dopant barrier region is also included and is disposed between the higher and lower doped regions of the second region of the optical waveguide.

Abstract: A doped barrier region included in an optical phase shifter is disclosed. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide and a second region of the optical waveguide. The second region of the optical waveguide includes a higher doped region of material and a lower doped region of material. An insulating region disposed between the first and second regions of the optical waveguide is also included. A first portion the higher doped region is disposed proximate to the insulating region. A dopant barrier region is also included and is disposed between the higher and lower doped regions of the second region of the optical waveguide.

Abstract: A doped barrier region included in an optical phase shifter is disclosed. In one embodiment, an apparatus according to embodiments of the present invention includes a first region of an optical waveguide and a second region of the optical waveguide. The second region of the optical waveguide includes a higher doped region of material and a lower doped region of material. An insulating region disposed between the first and second regions of the optical waveguide is also included. A first portion the higher doped region is disposed proximate to the insulating region. A dopant barrier region is also included and is disposed between the higher and lower doped regions of the second region of the optical waveguide.

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: According to the invention, systems, apparatus and methods are disclosed for optically enabling a circuit component in a large scale integrated circuit. In one embodiment, the invention is a circuit comprising a light sensing device for producing a signal in response to sensing light, an optic function subcircuit, and a switch connected to the light sensing device and to the optic function subcircuit for activating the optic function subcircuit when light is sensed. The light sensing device is preferably a phototransistor and a light sensing circuit is preferably placed between the light sensing device and the switch for amplifying and conditioning the light sensing signal. The optic function subcircuit can be an optical modulator, an optical receiver or any other device that is to be operated and powered only when incident light is present.

Abstract: An antifuse circuit includes a capacitor and a detector. The capacitor is formed using standard MOS processes in a well. The gate serves as one electrode and the well serving as another electrode of the capacitor. The antifuse is programmed by externally provided radiation that can rupture the gate oxide so that the gate and well can contact each other. The gate and well form a PN junction, transforming the capacitor into a diode. The diode provides the conductive path of the programmed antifuse.

Abstract: A temperature sensing and control method and apparatus. In one aspect of the present invention, an apparatus according to the teachings of the present invention includes an optical path disposed in semiconductor material, a grating disposed in the optical path, and a thermal probe including an optical sensor optically coupled to the grating to sense a spectral response of the grating. The thermal probe is adapted to determine a temperature of the optical path in which the grating is disposed in response to the spectral response of the grating.

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: A temperature sensing and control method and apparatus. In one aspect of the present invention, an apparatus according to the teachings of the present invention includes an optical path disposed in semiconductor material, a grating disposed in the optical path, and a thermal probe including an optical sensor optically coupled to the grating to sense a spectral response of the grating. The thermal probe is adapted to determine a temperature of the optical path in which the grating is disposed in response to the spectral response of the grating.

Abstract: Method and apparatus for adjusting the phase of an optical beam. In one aspect of the present invention, an optical device includes a substrate through which an optical beam is to be directed along an optical path. In one embodiment, the optical device includes an array of segments of optical phase-shifting structures along the path. In one embodiment, each respective one of the segments is to be selectively switched on or off to adjust a phase of the optical beam. In one embodiment, the optical phase-shifting structures include capacitive structures to induce the plasma optical effect to adjust the phase of an optical beam. In another embodiment, the optical phase-shifting structures include an electro-optic material such as Lithium Niobate.

Abstract: A temperature sensing and control method and apparatus. In one aspect of the present invention, an apparatus according to the teachings of the present invention includes an optical path disposed in semiconductor material. A four-terminal resistor is defined in the semiconductor material. At least a portion of the optical path is directed through the four-terminal resistor. The four-terminal resistor includes a first pair of terminals between which a probe current is to be injected. The four-terminal resistor also includes a second pair of terminals between which a voltage drop is to be measured so as to determine a resistance along the portion of the optical path directed through the four-terminal resistor. Temperature may be derived from the determined resistance of the four-terminal resistor. In one embodiment, the temperature of the semiconductor material may then be controlled with a heater in response to the derived temperature.

Abstract: According to the invention, systems, apparatus and methods are disclosed for optically enabling a circuit component in a large scale integrated circuit. In one embodiment, the invention is a circuit comprising a light sensing device for producing a signal in response to sensing light, an optic function subcircuit, and a switch connected to the light sensing device and to the optic function subcircuit for activating the optic function subcircuit when light is sensed. The light sensing device is preferably a phototransistor and a light sensing circuit is preferably placed between the light sensing device and the switch for amplifying and conditioning the light sensing signal. The optic function subcircuit can be an optical modulator, an optical receiver or any other device that is to be operated and powered only when incident light is present.