Abstract: Systems, apparatus and methods for defining an impairment profile along a polarization quantum channel such as in terms of modal loss and decoherence. The disclosed impairment profile or characterization methods may be used as part of a tool such as to inform a network operator of a weakest span of the communication channel, thus facilitating optimal signal routing decisions.

Abstract: The present invention relates to a lightweight, high resolution portable ultrasound system using components and methods to improve connectivity and ease of use. A preferred embodiment includes an integrated system in which the beamformer control circuitry can be inserted into the host computer as a peripheral or within the processor housing.

Abstract: A hand-held ultrasound system includes integrated electronics within an ergonomic housing. The electronics includes control circuitry, beamforming and circuitry transducer drive circuitry. The electronics communicate with a host computer using an industry standard high speed serial bus. The ultrasonic imaging system is operable on a standard, commercially available, user computing device without specific hardware modifications, and is adapted to interface with an external application without modification to the ultrasonic imaging system to allow a user to gather ultrasonic data on a standard user computing device such as a PC, and employ the data so gathered via an independent external application without requiring a custom system, expensive hardware modifications, or system rebuilds.

Abstract: Various embodiments are directed to systems, apparatus and methods for characterizing evanescent coupling parameters of a waveguide coupled to a resonator through variation of their relative positions. Various embodiments extend a local coupling approach with novel fitting capabilities that robustly determine the bare resonator modes and coupling parameters with quantified residual error and coupling parameter uncertainty estimates.

Abstract: A supporting case for use with a smart device such as a smart phone to assist a visually impaired individual. The case has a lower surface for positioning over a viewing surface containing material to be viewed by the individual and a pocket configured and dimensioned to receive and support the smart device. The case includes one or both of a lifting system for lifting and holding the case hands-free at a pre-set distance above the material to be viewed and a distance viewing system to view material not underneath the case.

Abstract: A quantum key distribution system is deployed in an optical fiber network transporting classical data traffic. A source of entangled photon pairs is used to generate quantum keys. Classical data traffic is typically transported over channels in the C-band. If a pair of channels for transport of quantum data is available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in the C-band. If a pair of channels for transport of quantum data is not available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in a combined S-band and L-band. When a periodically-poled lithium niobate waveguide pumped with a laser is used for the source of entangled photon pairs, the output spectral properties are tuned by varying the temperature of the waveguide.

Abstract: A novel methodology for characterizing and calibrating an entangled photon distribution system is disclosed. The entangled photon distribution system includes at least a source of entangled photon pairs, two photon detectors which detect photons among two channels and a controller. The methodology includes: for at least two different operational setting levels of the source of entangled photon pairs, measuring count rates for photons detected by the two photon detectors, individually and coincidently; fitting the measured individual and coincidence count rate data for the at least two different operational setting levels with theoretical models of detection probability; and determining operational parameters of the system from the fitting.

Abstract: A hand-held ultrasound system includes integrated electronics within an ergonomic housing. The electronics includes control circuitry, beamforming and circuitry transducer drive circuitry. The electronics communicate with a host computer using an industry standard high speed serial bus. The ultrasonic imaging system is operable on a standard, commercially available, user computing device without specific hardware modifications, and is adapted to interface with an external application without modification to the ultrasonic imaging system to allow a user to gather ultrasonic data on a standard user computing device such as a PC, and employ the data so gathered via an independent external application without requiring a custom system, expensive hardware modifications, or system rebuilds.

Abstract: Methods and apparatuses are provided that compensate for the polarization dependent loss (PDL) of fiber-optic quantum channels. Compensation is accomplished by inserting a compensating PDL into another quantum channel carrying entangled photons that are entangled with photons in the first channel having losses that are to be compensated for. By selecting the optimum magnitude and orientation for the compensating PDL, compensation for the PDL in the first channel is maximized.

Abstract: A quantum key distribution system is deployed in an optical fiber network transporting classical data traffic. A source of entangled photon pairs is used to generate quantum keys. Classical data traffic is typically transported over channels in the C-band. If a pair of channels for transport of quantum data is available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in the C-band. If a pair of channels for transport of quantum data is not available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in a combined S-band and L-band. When a periodically-poled lithium niobate waveguide pumped with a laser is used for the source of entangled photon pairs, the output spectral properties are tuned by varying the temperature of the waveguide.

Abstract: Methods and apparatuses are provided that compensate for the polarization dependent loss (PDL) of fiber-optic quantum channels. Compensation is accomplished by inserting a compensating PDL into another quantum channel carrying entangled photons that are entangled with photons in the first channel having losses that are to be compensated for. By selecting the optimum magnitude and orientation for the compensating PDL, compensation for the PDL in the first channel is maximized.

Abstract: A quantum key distribution system is deployed in an optical fiber network transporting classical data traffic. A source of entangled photon pairs is used to generate quantum keys. Classical data traffic is typically transported over channels in the C-band. If a pair of channels for transport of quantum data is available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in the C-band. If a pair of channels for transport of quantum data is not available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in a combined S-band and L-band. When a periodically-poled lithium niobate waveguide pumped with a laser is used for the source of entangled photon pairs, the output spectral properties are tuned by varying the temperature of the waveguide.

Abstract: Methods and systems for measuring interferometric visibility of telescopic signals using resources having imperfect quantum entanglement are disclosed. The novel methodology employed by embodiments of the present invention takes into account the difficulty in creating entanglement between distance telescopes, and describes how to incorporate problems associated with distributing quantum entanglement into the measurement procedure. This allows the distance that two telescopes in an optical array are spaced apart to be increased while still interacting.

Abstract: A novel methodology for characterizing and calibrating an entangled photon distribution system is disclosed. The entangled photon distribution system includes at least a source of entangled photon pairs, two photon detectors which detect photons among two channels and a controller. The methodology includes: for at least two different operational setting levels of the source of entangled photon pairs, measuring count rates for photons detected by the two photon detectors, individually and coincidently; fitting the measured individual and coincidence count rate data for the at least two different operational setting levels with theoretical models of detection probability; and determining operational parameters of the system from the fitting.

Abstract: Operational parameters of a single-photon detector are determined with a continuous wave laser source. At a fixed trigger, a dark count probability and a series of count probabilities at different optical powers are determined. A particular optical power is selected by using a wide-range variable attenuator to attenuate the optical power of the continuous wave laser. The dark count probability and the count probabilities are determined for different trigger rates. The operational parameters include efficiency, afterpulsing constant, and detrap time. The operational parameters are computed by fitting the computed dark count probabilities and count probabilities to a user-defined relationship.

Abstract: Methods and systems for measuring interferometric visibility of telescopic signals using resources having imperfect quantum entanglement are disclosed. The novel methodology employed by embodiments of the present invention takes into account the difficulty in creating entanglement between distance telescopes, and describes how to incorporate problems associated with distributing quantum entanglement into the measurement procedure. This allows the distance that two telescopes in an optical array are spaced apart to be increased while still interacting.

Abstract: The present invention relates to a lightweight, high resolution portable ultrasound system using components and methods to improve connectivity and ease of use. A preferred embodiment includes an integrated system in which the beamformer control circuitry can be inserted into the host computer as a peripheral or within the processor housing.

Abstract: Quantum networking systems and methods for routing entangled photons pairs are described herein. One quantum networking system includes entangled photon sources which generate entangled photons; optical output ports; a reconfigurable switching network connecting to the entangled photon sources and the output ports, which include a regular repeating structure of optical crossbar switches and interconnections for selectively routing individual ones of entangled photons pairs input to the network to and amongst the outputs; and a control module. The control module is configured to receive a request for entangled photons at the output ports; execute a routing algorithm to determine the state of the switches in the reconfigurable switching network to satisfy the request; and generate and transmit control signals to the switching network in order to set the states of the switches according to the executed routing algorithm. The reconfigurable switching network may be a Beneš or a banyan-type network architecture.

Abstract: A method for determining a network configuration for the delivery of entangled photons individually to a plurality of users, the network comprising a plurality of inputs, switches, and outputs operatively connected by optical fibers; the plurality of switches being switchable between two states; the method comprising: determining the minimum number of switches necessary to deliver entangled photon pairs from a predetermined number of sources to a predetermined number of users, minimizing the loss experienced by an entangled photon passing through the switches by minimizing the number of switches that any one photon passes through by selecting only nondominated switch configurations; determining the minimum number of equivalent network switch configurations and eliminating all but one of the equivalent network switch configurations; and selecting an optimum network configuration by which the plurality of inputs and the plurality of outputs are operatively interconnected using a minimum number of switches in

Abstract: The present invention relates to a lightweight, high resolution portable ultrasound system using components and methods to improve connectivity and ease of use. A preferred embodiment includes an integrated system in which the beamformer control circuitry can be inserted into the host computer as a peripheral or within the processor housing.