Abstract: Mach-Zehnder interferometers comprise heater elements configured to have projections in the plane of optical waveguides positioned such that two adjacent sections of one optical waveguide arms are heated by a common heater element. The heater and at least a substantial section of the heated waveguide segments can be curved. Configurations of an optical waveguide arm can comprise an outer curved heated section, an inner curved heated section, and a loopback waveguide section connecting the outer curved heated section and the inner curved heated section, with average radius of curvature selected to form an open accessible space. Appropriate configurations of the two optical waveguide arms provide for nested configurations of the arms that provide for a compact structure for the interferometer.

Abstract: Mach-Zehnder interferometers comprise heater elements configured to have projections in the plane of optical waveguides positioned such that two adjacent sections of one optical waveguide arms are heated by a common heater element. The heater and at least a substantial section of the heated waveguide segments can be curved. Configurations of an optical waveguide arm can comprise an outer curved heated section, an inner curved heated section, and a loopback waveguide section connecting the outer curved heated section and the inner curved heated section, with average radius of curvature selected to form an open accessible space. Appropriate configurations of the two optical waveguide arms provide for nested configurations of the arms that provide for a compact structure for the interferometer.

Abstract: Energy efficient thermo-optic phase shifters have a configuration with two sections of a waveguide adjacent for heating by a common heater. A loop section can connect the two heated waveguide sections. Further improved efficiency can be achieved in which the heated sections are curved to allow closer placement of the adjacent waveguides. The heater can be curved to follow the configuration of the curved heated waveguide sections. Energy efficiency gains can be up to approximately a factor of two over corresponding traditional thermo-optical phase shifter designs.

Abstract: Mach-Zehnder interferometers comprise heater elements configured to have projections in the plane of optical waveguides positioned such that two adjacent sections of one optical waveguide arms are heated by a common heater element. The heater and at least a substantial section of the heated waveguide segments can be curved. Configurations of an optical waveguide arm can comprise an outer curved heated section, an inner curved heated section, and a loopback waveguide section connecting the outer curved heated section and the inner curved heated section, with average radius of curvature selected to form an open accessible space. Appropriate configurations of the two optical waveguide arms provide for nested configurations of the arms that provide for a compact structure for the interferometer.

Abstract: Energy efficient thermo-optic phase shifters have a configuration with two sections of a waveguide adjacent for heating by a common heater. A loop section can connect the two heated waveguide sections. Further improved efficiency can be achieved in which the heated sections are curved to allow closer placement of the adjacent waveguides. The heater can be curved to follow the configuration of the curved heated waveguide sections. Energy efficiency gains can be up to approximately a factor of two over corresponding traditional thermo-optical phase shifter designs.

Abstract: Mach-Zehnder interferometers comprise heater elements configured to have projections in the plane of optical waveguides positioned such that two adjacent sections of one optical waveguide arms are heated by a common heater element. The heater and at least a substantial section of the heated waveguide segments can be curved. Configurations of an optical waveguide arm can comprise an outer curved heated section, an inner curved heated section, and a loopback waveguide section connecting the outer curved heated section and the inner curved heated section, with average radius of curvature selected to form an open accessible space. Appropriate configurations of the two optical waveguide arms provide for nested configurations of the arms that provide for a compact structure for the interferometer.

Abstract: Optical networks can comprise a branch structure with the de-multiplexing/multiplexing structure that operates to disperse a plurality of optical bands. Thus, the optical network comprises an optical network connection with a common optical channel, a plurality of de-multiplexed branch optical service connections and the de-multiplexing/multiplexing structure. In some embodiments, one optical band can be used to deliver input from a common channel to the branch node and the other optical band can carry output along the common channel from the branch node. The de-multiplexing/multiplexing element can be an arrayed waveguide grating. The AWG can have desirable architecture to efficiently provide the corresponding functions with respect to the two optical bands. Appropriate photodetectors and light sources can be associated with the AWG.

Abstract: Optical networks can comprise a branch structure with the de-multiplexing/multiplexing structure that operates to disperse a plurality of optical bands. Thus, the optical network comprises an optical network connection with a common optical channel, a plurality of de-multiplexed branch optical service connections and the de-multiplexing/multiplexing structure. In some embodiments, one optical band can be used to deliver input from a common channel to the branch node and the other optical band can carry output along the common channel from the branch node. The de-multiplexing/multiplexing element can be an arrayed waveguide grating. The AWG can have desirable architecture to efficiently provide the corresponding functions with respect to the two optical bands. Appropriate photodetectors and light sources can be associated with the AWG.

Abstract: A linearized thermal and optical model of an optical integrated circuit can be used to temperature-stabilize one or more optical elements of the circuit using active temperature regulation. To stabilize a single optical element, a temperature sensor and a heater can be provided proximate to the grating. Thermal and optical coefficients can be then used to select an appropriate temperature set-point for the temperature controller that receives readings from the sensor and determines the power dissipated in the heater. Multiple optical elements can be stabilized individually, using the same process and lumping cross-heating factors together with other environmental factors. Alternatively, multiple AWG's can be stabilized using fewer sensors than optical elements, by stabilizing one of the optical elements in the same manner as in the case of a single optical elements, and determining power dissipated in the heaters of the remaining optical elements based on the linearized model.

Abstract: A linearized thermal and optical model of an optical integrated circuit can be used to temperature-stabilize one or more optical elements of the circuit using active temperature regulation. To stabilize a single optical element, a temperature sensor and a heater can be provided proximate to the grating. Thermal and optical coefficients can be then used to select an appropriate temperature set-point for the temperature controller that receives readings from the sensor and determines the power dissipated in the heater. Multiple optical elements can be stabilized individually, using the same process and lumping cross-heating factors together with other environmental factors. Alternatively, multiple AWG's can be stabilized using fewer sensors than optical elements, by stabilizing one of the optical elements in the same manner as in the case of a single optical elements, and determining power dissipated in the heaters of the remaining optical elements based on the linearized model.

Abstract: An optical device with a non-rectilinearly shaped optical integrated circuit over a substantially flat portion of a riser, the riser also equipped with a relief structure that is in thermal contact with a stabilizing brace that is in turn connected to two portions of the non-rectilinearly shaped optical integrated circuit. The non-rectilinearly shaped optical integrated circuit exhibits reduced center wavelength drift.

Abstract: A linearized thermal and optical model of an optical integrated circuit can be used to temperature-stabilize one or more optical elements of the circuit using active temperature regulation. To stabilize a single optical element, such as an arrayed waveguide grating (AWG), a temperature sensor and a heater can be provided proximate to the grating. Thermal and optical coefficients can be then used to select an appropriate temperature set-point for the temperature controller that receives readings from the sensor and determines the power dissipated in the heater. Multiple AWG's can be stabilized individually, using the same process and lumping cross-heating factors together with other environmental factors. Alternatively, multiple AWG's can be stabilized using fewer sensors than AWG's, by stabilizing one of the AWG's in the same manner as in the case of a single AWG, and determining power dissipated in the heaters of the remaining AWG's based on the linearized model.

Abstract: An optical device with a non-rectilinearly shaped optical integrated circuit over a substantially flat portion of a riser, the riser also equipped with a relief structure that is in thermal contact with a stabilizing brace that is in turn connected to two portions of the non-rectilinearly shaped optical integrated circuit. The non-rectilinearly shaped optical integrated circuit exhibits reduced center wavelength drift.

Abstract: A linearized thermal and optical model of an optical integrated circuit can be used to temperature-stabilize one or more optical elements of the circuit using active temperature regulation. To stabilize a single optical element, such as an arrayed waveguide grating (AWG), a temperature sensor and a heater can be provided proximate to the grating. Thermal and optical coefficients can be then used to select an appropriate temperature set-point for the temperature controller that receives readings from the sensor and determines the power dissipated in the heater. Multiple AWG's can be stabilized individually, using the same process and lumping cross-heating factors together with other environmental factors. Alternatively, multiple AWG's can be stabilized using fewer sensors than AWG's, by stabilizing one of the AWG's in the same manner as in the case of a single AWG, and determining power dissipated in the heaters of the remaining AWG's based on the linearized model.