Abstract: Methods and devices implementing a combination of multi-dimensional pulse position modulation (PPM) with wavelength division multiplexing (WDM) or wavelength division multiplexing multiple access (WDMA) for long range space communications are disclosed. The described multi-dimensional PPM scheme can use the laser wavelength and/or polarization as the additional dimension(s) to the time dimension. Through examples it is shown that the disclosed teachings result in a higher photon information efficiency. Various exemplary embodiments are also presented to highlight the applications benefiting from the disclosed methods and devices.

Abstract: Methods and devices implementing a combination of multi-dimensional pulse position modulation (PPM) with wavelength division multiplexing (WDM) or wavelength division multiplexing multiple access (WDMA) for long range space communications are disclosed. The described multi-dimensional PPM scheme can use the laser wavelength and/or polarization as the additional dimension(s) to the time dimension. Through examples it is shown that the disclosed teachings result in a higher photon information efficiency. Various exemplary embodiments are also presented to highlight the applications benefiting from the disclosed methods and devices.

Abstract: Methods and devices implementing a combination of multi-dimensional pulse position modulation (PPM) with wavelength division multiplexing (WDM) or wavelength division multiplexing multiple access (WDMA) for long range space communications are disclosed. The described multi-dimensional PPM scheme can use the laser wavelength and/or polarization as the additional dimension(s) to the time dimension. Through examples it is shown that the disclosed teachings result in a higher photon information efficiency. Various exemplary embodiments are also presented to highlight the applications benefiting from the disclosed methods and devices.

Abstract: Systems and methods described herein provide a thermally compensated waveguide structure having a thermal index profile configured to correct thermal aberrations caused by temperature gradients in a fast axis direction and/or correct other forms of distortions in an output beam generated by the waveguide structure. The waveguide structure includes a core region, one or more cladding, and one or more heat sinks. A geometry of these portions with respect to each other can provide a cold refractive index profile such that a cold refractive index value of a portion of the core region is less than a cold refractive index value of at least one of the one or more cladding regions. Responsive to thermal compensation, the cold refractive index profile is modified, through addition of a thermal index profile, to form a hot index profile having attributes including good overlap of the fundamental mode with the gain profile and mode clean-up through gain discrimination against higher order modes.

Abstract: A system includes a master oscillator configured to generate a low-power optical beam. The system also includes a planar waveguide (PWG) amplifier having one or more laser diode pump arrays, a planar waveguide, and a light pipe. The one or more laser diode pump arrays are configured to generate pumplight. The planar waveguide is configured to generate a high-power optical beam using the low-power optical beam and the pumplight. The light pipe is configured to substantially homogenize the pumplight and to inject the homogenized pumplight into the planar waveguide. The light pipe is also configured to inject the low-power optical beam into the planar waveguide.

Abstract: Systems and methods described herein provide a thermally compensated waveguide structure having a thermal index profile configured to correct thermal aberrations caused by temperature gradients in a fast axis direction and/or correct other forms of distortions in an output beam generated by the waveguide structure. The waveguide structure includes a core region, one or more cladding, and one or more heat sinks. A geometry of these portions with respect to each other can provide a cold refractive index profile such that a cold refractive index value of a portion of the core region is less than a cold refractive index value of at least one of the one or more cladding regions. Responsive to thermal compensation, the cold refractive index profile is modified, through addition of a thermal index profile, to form a hot index profile having attributes including good overlap of the fundamental mode with the gain profile and mode clean-up through gain discrimination against higher order modes.

Abstract: A method includes forming a coating that covers at least part of a conduction substrate, where the conduction substrate is configured to transport thermal energy. The method also includes forming at least part of an optical waveguide on the coating. The optical waveguide includes multiple cladding layers and a core, and the optical waveguide is configured to transport optical signals. The conduction substrate, the coating, and the optical waveguide form an integrated monolithic waveguide structure.

Abstract: A high-speed analog-to-digital converter can produce a digital signal representative of an analog input electrical signal. An optical amplitude modulator can modulate an input optical pulse train using the analog input electrical signal. An optical splitter can split the modulated optical pulse train into a plurality of modulated optical pulse trains. Optical path delays can stagger in time the modulated optical pulse trains to form a plurality of time-staggered modulated optical pulse trains. Demodulators can detect and filter the time-staggered modulated optical pulse trains to form a respective plurality of time-averaged voltages. Analog-to-digital converters can output a respective plurality of digital time series representative of the respective time-averaged voltages. An interleaver can aggregate the plurality of digital time series to form the digital signal, which has a sample rate greater than a repetition rate of the input optical pulse train.

Abstract: An analog-to-digital converter can produce a digital signal representative of an analog input electrical signal. An optical amplitude modulator can modulate an input optical pulse train using the analog input electrical signal to produce a first modulated optical pulse train. An optical splitter can split the first modulated optical pulse train into a plurality of modulated optical pulse trains. A plurality of detectors can convert the plurality of modulated optical pulse trains into respective modulated voltage pulse trains. A plurality of comparators and a decoder, arranged in a flash converter topology, can receive the modulated voltage pulse trains and output the digital signal representative of the analog input electrical signal using a timing reference derived from the input optical pulse train. Using a relatively high-precision input optical pulse train, such as a Kerr Comb, can produce a relatively high-accuracy analog-to-digital converter.

Abstract: An apparatus includes a four-braid resistive heater, which includes a conductive structure configured to transport electrical currents and to generate heat based on the electrical currents. The conductive structure has first, second, third, and fourth electrical conductors. The first and second electrical conductors are looped around each other along a length of the conductive structure. The third and fourth electrical conductors are looped around each other along the length of the conductive structure. Loops formed with the first and second conductors are interleaved with loops formed with the third and fourth conductors along the length of the conductive structure. The first and third electrical conductors can be electrically coupled together, and the second and fourth electrical conductors can be electrically coupled together.

Abstract: A system includes a master oscillator configured to generate a low-power optical beam. The system also includes a planar waveguide (PWG) amplifier having one or more laser diode pump arrays, a planar waveguide, and a light pipe. The one or more laser diode pump arrays are configured to generate pumplight. The planar waveguide is configured to generate a high-power optical beam using the low-power optical beam and the pumplight. The light pipe is configured to substantially homogenize the pumplight and to inject the homogenized pumplight into the planar waveguide. The light pipe is also configured to inject the low-power optical beam into the planar waveguide.

Abstract: A Fabry Perot resonator spacer is provided. The Fabry Perot resonator spaced includes a tetrahedral body, the tetrahedral body being made of a material having a Poisson ratio and defining a plurality of triangular faces, a plurality of edges, and a plurality of corners, wherein each one of the plurality of corners is truncated to form a mounting surface in a mounting plane. The spacer further includes a first mirror channel configured to receive a first optical element, a second mirror channel configured to receive a second optical element, and an optical cavity extending linearly through the tetrahedral body between the first mirror channel and the second mirror channel.

Abstract: A method includes forming a coating that covers at least part of a conduction substrate, where the conduction substrate is configured to transport thermal energy. The method also includes forming at least part of an optical waveguide on the coating. The optical waveguide includes multiple cladding layers and a core, and the optical waveguide is configured to transport optical signals. The conduction substrate, the coating, and the optical waveguide form an integrated monolithic waveguide structure.

Abstract: An optical fiber having a large mode area for high power applications and geometrically configured for single-mode operation. One example of an optical fiber system includes a mandrill and an optical fiber helically coiled about the mandrill with a preselected bend radius. The optical fiber includes a core having a high aspect ratio elongated cross-section, wherein the core is narrower in a fast-axis direction and wider in a slow-axis direction, the core including an annular protrusion that is Gaussian in transverse cross-section and has a width in the slow-axis direction and an annular extension in the fast-axis direction, and wherein a ratio of the width, the annular extension, and the bend radius is selected for single-mode operation of the optical fiber.

Abstract: A Fabry Perot resonator spacer is provided. The Fabry Perot resonator spaced includes a tetrahedral body, the tetrahedral body being made of a material having a Poisson ratio and defining a plurality of triangular faces, a plurality of edges, and a plurality of corners, wherein each one of the plurality of corners is truncated to form a mounting surface in a mounting plane. The spacer further includes a first mirror channel configured to receive a first optical element, a second mirror channel configured to receive a second optical element, and an optical cavity extending linearly through the tetrahedral body between the first mirror channel and the second mirror channel.

Abstract: Signal filter designs and techniques use a signal filter of a given order to achieve a higher order filter operation than what the filter is designed for. In various implementations, the present signal filter designs and techniques allow achieving desired high order filter operation without using a high order filter. Specific examples are provided to use a double pass configuration to feed a once filtered signal by a filter back to the filter to filter the feedback signal for the second time and a Sagnac interferometer configuration to cause interference between two once filtered signals.

Abstract: An apparatus includes a four-braid resistive heater, which includes a conductive structure configured to transport electrical currents and to generate heat based on the electrical currents. The conductive structure has first, second, third, and fourth electrical conductors. The first and second electrical conductors are looped around each other along a length of the conductive structure. The third and fourth electrical conductors are looped around each other along the length of the conductive structure. Loops formed with the first and second conductors are interleaved with loops formed with the third and fourth conductors along the length of the conductive structure. The first and third electrical conductors can be electrically coupled together, and the second and fourth electrical conductors can be electrically coupled together.

Abstract: Photonic devices and techniques based on tunable single sideband (SSB) modulation in whispering gallery mode resonators formed of different poled electro-optic domains and to support whispering gallery modes circulating in the optical resonator to effectuate a single sideband (SSB) on only one side of the laser frequency without having a mirror image sideband on the other side of the laser frequency.

Abstract: Optical gyroscope devices based on optical whispering gallery mode resonators that measure rotations based on rotation-induced optical phase shift in optical whispering gallery mode resonators.

Abstract: An optical device including a whispering gallery mode (WGM) optical resonator configured to support one or more whispering gallery modes; and a photodetector optically coupled to an exterior surface of the optical resonator to receive evanescent light from the optical resonator to detect light inside the optical resonator.