Abstract: A device for controlling clearance between the tips of rotating blades of an aircraft turbomachine and a casing. An air circulation path allows air to be blown onto the casing in order to change its temperature. In addition, heating means heat the circulating air.

Abstract: A device (e.g., a photonic multiplexer) is provided that includes a plurality of first switches. Each first switch in the plurality of first switches includes a plurality of first channels. Each first switch is configured to shift photons in the plurality of first channels by zero or more channels, based on first configuration information provided to the first switch. The device further includes a plurality of second switches. Each second switch includes a plurality of second channels. Each second channel is coupled with a respective first channel from a distinct first switch of the plurality of first switches. Each second switch is configured to shift photons in the plurality of second channels by zero or more channels, based on second configuration information provided to the second switch.

Abstract: A device includes a first semiconductor layer; a portion of a second semiconductor layer disposed on the first semiconductor layer; and a third semiconductor layer including a first region disposed on the portion of the second semiconductor layer and a second region disposed on the first semiconductor layer. A thickness of the first region is less than a predefined thickness. The device also includes an etch stop layer disposed on the third semiconductor layer; a plurality of distinct portions of a fourth semiconductor layer disposed on the etch stop layer and exposing one or more distinct portions of the etch stop layer over the portion of the second semiconductor layer; and a plurality of distinct portions of a superconducting layer disposed on the plurality of distinct portions of the fourth semiconductor layer and the exposed one or more distinct portions of the etch stop layer.

Abstract: A device (e.g., a photonic multiplexer) is provided that includes a plurality of first switches. Each first switch in the plurality of first switches includes a plurality of first channels. Each first switch is configured to shift photons in the plurality of first channels by zero or more channels, based on first configuration information provided to the first switch. The device further includes a plurality of second switches. Each second switch includes a plurality of second channels. Each second channel is coupled with a respective first channel from a distinct first switch of the plurality of first switches. Each second switch is configured to shift photons in the plurality of second channels by zero or more channels, based on second configuration information provided to the second switch.

Abstract: A device (e.g., a photonic multiplexer) is provided that includes a plurality of first switches. Each first switch in the plurality of first switches includes a plurality of first channels. Each first switch is configured to shift photons in the plurality of first channels by zero or more channels, based on first configuration information provided to the first switch. The device further includes a plurality of second switches. Each second switch includes a plurality of second channels. Each second channel is coupled with a respective first channel from a distinct first switch of the plurality of first switches. Each second switch is configured to shift photons in the plurality of second channels by zero or more channels, based on second configuration information provided to the second switch.

Abstract: A device includes a first semiconductor layer; a portion of a second semiconductor layer disposed on the first semiconductor layer; and a third semiconductor layer including a first region disposed on the portion of the second semiconductor layer and a second region disposed on the first semiconductor layer. A thickness of the first region is less than a predefined thickness. The device also includes an etch stop layer disposed on the third semiconductor layer; a plurality of distinct portions of a fourth semiconductor layer disposed on the etch stop layer and exposing one or more distinct portions of the etch stop layer over the portion of the second semiconductor layer; and a plurality of distinct portions of a superconducting layer disposed on the plurality of distinct portions of the fourth semiconductor layer and the exposed one or more distinct portions of the etch stop layer.

Abstract: A method includes receiving input light having an input wavelength in a first optical resonator for causing resonance of the input light in the first optical resonator. The first optical resonator includes a non-linear optical medium. The method also includes converting at least a portion of the input light to a combination of first output light having a first output wavelength that is different from the input wavelength and second output light having a second output wavelength that is different from the input wavelength and the first output wavelength by passing the input light through the non-linear optical medium. The method further includes causing resonance of the first output light and the second output light in a second optical resonator. A portion of the first optical resonator is coupled to a portion of the second optical resonator.

Abstract: An aircraft turbine casing configured to carry a set of ring sectors that partly delimits a conduit inside which a gas flow passes through the turbine, including a dynamic mechanism adjusting radial position of ring sectors, an upstream radial lug that connects an upstream end of each ring sector to the casing, and a downstream radial lug that connects a downstream end of each ring sector to the casing. The upstream lug is made as a single piece with the casing and is directly connected to the upstream end of each ring sector.

Abstract: A device (e.g., a photonic multiplexer) is provided that includes a plurality of first switches. Each first switch in the plurality of first switches includes a plurality of first channels. Each first switch is configured to shift photons in the plurality of first channels by zero or more channels, based on first configuration information provided to the first switch. The device further includes a plurality of second switches. Each second switch includes a plurality of second channels. Each second channel is coupled with a respective first channel from a distinct first switch of the plurality of first switches. Each second switch is configured to shift photons in the plurality of second channels by zero or more channels, based on second configuration information provided to the second switch.

Abstract: Techniques disclosed herein relate to photon sources with high spectral purity and high brightness. In one embodiment, a photon-pair source includes a pump waveguide, a first resonator coupled to the pump waveguide to couple pump photons from the pump waveguide into the first resonator, a second resonator coupled to the first resonator, and an output waveguide coupled to the second resonator. The second resonator is configured to convert the pump photons into photon pairs. The second resonator and the first resonator are configured to cause a coupling-induced resonance splitting in the second resonator or the first resonator. The second resonator and the output waveguide are configured to couple the photon pairs from the second resonator into the output waveguide. In some embodiments, the photo-pair source includes one or more tuners for tuning at least one of the first resonator or the second resonator.

Abstract: A device (e.g., a photonic multiplexer) is provided that includes a plurality of first switches. Each first switch in the plurality of first switches includes a plurality of first channels. Each first switch is configured to shift photons in the plurality of first channels by zero or more channels, based on first configuration information provided to the first switch. The device further includes a plurality of second switches. Each second switch includes a plurality of second channels. Each second channel is coupled with a respective first channel from a distinct first switch of the plurality of first switches. Each second switch is configured to shift photons in the plurality of second channels by zero or more channels, based on second configuration information provided to the second switch.

Abstract: A device includes a first semiconductor layer; a portion of a second semiconductor layer disposed on the first semiconductor layer; and a third semiconductor layer including a first region disposed on the portion of the second semiconductor layer and a second region disposed on the first semiconductor layer. A thickness of the first region is less than a predefined thickness. The device also includes an etch stop layer disposed on the third semiconductor layer; a plurality of distinct portions of a fourth semiconductor layer disposed on the etch stop layer and exposing one or more distinct portions of the etch stop layer over the portion of the second semiconductor layer; and a plurality of distinct portions of a superconducting layer disposed on the plurality of distinct portions of the fourth semiconductor layer and the exposed one or more distinct portions of the etch stop layer.

Abstract: A photon source device includes a substrate and a first waveguide arranged on the substrate. The first waveguide is coupled with a first pair of reflectors defining a first resonant cavity in the first waveguide. The first resonant cavity is configured for outputting a first output wavelength and a second output wavelength. The first pair of reflectors include a partial reflector for the first output wavelength and a partial reflector for the second output wavelength. The photon source device further includes a second pair of reflectors defining a second resonant cavity that intersects with the first resonant cavity. The second resonant cavity is configured for receiving an input wavelength distinct from the first and the second output wavelengths. A first reflector and a second reflector of the second pair of reflectors have a first reflectance and a second reflectance for the input wavelength, respectively.

Abstract: There is presented a spectroscopic apparatus and method wherein an input light source that inputs pump light to a photon pair source. The photon pair source converts pump photons into signal and idler photon pairs. The photon pair source is, in some of examples described herein, tuneable so that the wavelength of the signal and idler photons can be changed by application of a tuning means. At least one of the signal and idler photons is made incident upon a medium under test. A heralding detection apparatus is used to detect any signal and idler photons output from the spectroscopy apparatus, wherein at least one of the photons of the pair has interacted with or been operated upon by the medium under test.

Abstract: There is presented an optical apparatus comprising first and second photon pair sources configured to convert at least one pump light photon into a first and second correlated signal and idler photon pairs. In one example, the apparatus is configured to use one of the signal and idler photons from the first correlated photon pair for controlling the conversion of the pump light photon in the second photon pair source. The apparatus may configured such that, at least one of the signal and idler photons from the first correlated photon pair is output from the first photon pair source onto an optical path wherein at least one of the signal and idler photons from the second correlated photon pair is output from the second photon pair source onto the optical path. A method is also provided for outputting one or more photons using the optical apparatus.

Abstract: There is presented an optical apparatus comprising first and second photon pair sources configured to convert at least one pump light photon into a first and second correlated signal and idler photon pairs. In one example, the apparatus is configured to use one of the signal and idler photons from the first correlated photon pair for controlling the conversion of the pump light photon in the second photon pair source. The apparatus may configured such that, at least one of the signal and idler photons from the first correlated photon pair is output from the first photon pair source onto an optical path wherein at least one of the signal and idler photons from the second correlated photon pair is output from the second photon pair source onto the optical path. A method is also provided for outputting one or more photons using the optical apparatus.

Abstract: A method controlling a clearance between tips of blades of a turbine rotor of a gas turbine aircraft engine and a ring-shaped turbine shroud of a housing surrounding the blades, the method including: controlling flow and/or temperature of air directed toward the housing according to an estimate of the clearance, the estimate of the clearance is determined upon start-up of the aircraft engine, according to a temperature measured by a temperature sensor including a sensitive element positioned in a free space of the aircraft engine.

Abstract: There is presented a spectroscopic apparatus and method wherein an input light source that inputs pump light to a photon pair source. The photon pair source converts pump photons into signal and idler photon pairs. The photon pair source is, in some of examples described herein, tuneable so that the wavelength of the signal and idler photons can be changed by application of a tuning means. At least one of the signal and idler photons is made incident upon a medium under test. A heralding detection apparatus is used to detect any signal and idler photons output from the spectroscopy apparatus, wherein at least one of the photons of the pair has interacted with or been operated upon by the medium under test.

Abstract: An integrated optical device and method for generating photons by manipulating path entanglement is provided. An integrated optical splitter splits pump light between two interferometer arms wherein each arm comprises a substantially identical photon pair source configured to be able to convert at least one pump light photon into a signal and idler photon pair. An integrated optical combiner device in optical communication with a first and a second optical output path interferes light from the first and second arms and outputs the signal and idler photons by bunching the signal and idler photons together in one of the optical output paths, or anti-bunching the signal photon in one output path and the corresponding idler photon in the other optical output path.

Abstract: An integrated optical device and method for generating photons by manipulating path entanglement is provided. An integrated optical splitter splits pump light between two interferometer arms wherein each arm comprises a substantially identical photon pair source configured to be able to convert at least one pump light photon into a signal and idler photon pair. An integrated optical combiner device in optical communication with a first and a second optical output path interferes light from the first and second arms and outputs the signal and idler photons by bunching the signal and idler photons together in one of the optical output paths, or anti-bunching the signal photon in one output path and the corresponding idler photon in the other optical output path.