Her Majesty the Queen in Right of Canada as Represented by the Minister of Industry Through the Communications Research Centre Canada

National Research Council of Canada

Her Majesty the Queen in Right of Canada, as Represented by the Minister

Jds Fitel Inc.

Other

Her Majesty the Queen in Right of Canada, as Represented by the Ministry of Industry

Her Majesty the Queen in Right of Canada, as Represented by the Minister of Industry Through the Communications Research Centre

Her Majesty in Right of Canada as Represented by the Minister of Industry

Stephen J Mihailov

Ping Lu

Dan Grobnic

Huimin Ding

Robert Walker

Christopher W Smelser

Xiaoli Dai

David Coulas

Gino Cuglietta

Cyril Hnatovsky

George Henderson

Gary S Duck

Derwyn C Johnson

Francois C Bilodeau

Kenneth O Hill

Mark Farries

Koichi Abe

Jacques Albert

Rune Lausten

Robert B Walker

Benoit Simard

Bernard Y Malo

Mario Caron

Jingwen Guan

Jinghui Li

Benjamin J Sussman

David Henry Cushing

Philip J Bustard

Howard Rideout

Claire Callender

Duncan G England

Chantal Blanchetiere

John Oldham

Nurmemet Abdukerim

Kasthuri De Silva

Kyrylo Hnatovsky

Haimin Ding

Joe Seregelyi

Stéphane Paquet

Jianping Yao

The present invention provides an efficient quantum memory for storing a quantum state of light, such as a photon, for a temporary period of time in a fibre-integrated optical cavity and then recall the quantum state of light and quantum information at a later time with a high probability of success. The present invention uses a nonlinear optical switching mechanism to modify at least one property of the quantum light, or cavity, to trap the quantum light in the optical cavity. Subsequent application of the nonlinear optical switching mechanism switches at least one property of the stored quantum light, or cavity, to release the quantum light from the optical cavity. The present invention also provides quasi-deterministic single-photon generation by temporal multiplexing of a photon pair source integrated within the cavity.

Fibre optic integrated quantum memory for light

An apparatus, method and system are set forth for detection of fluids using Bragg grating sensors, wherein the Bragg grating sensing element comprises an optical fiber having a Bragg grating inscribed therein characterized by optical properties that are dependent upon the periodicity and effective refractive index of the grating, and a package for subjecting the Bragg grating to a change in strain when contacted by a fluid such that periodicity and effective refractive index of the grating changes, whereby when interrogated with laser light any such change in periodicity and effective refractive index may be detected.

Apparatus, method and system for detecting presence of a fluid

A method and apparatus for inscribing a Bragg grating in an optical waveguide, comprising: providing electromagnetic radiation from an ultrashort pulse duration laser, wherein the electromagnetic radiation has a pulse duration of less than or equal to 5 picoseconds, and wherein the wavelength of the electromagnetic radiation has a characteristic wavelength in the wavelength range from 150 nanometers (nm) to 2.0 microns (μm): providing cylindrical focusing optics corrected for spherical aberration: providing a diffractive optical element that when exposed to the focused ultrashort laser pulse, creates an interference pattern on the optical waveguide, wherein the irradiation step comprises irradiating a surface of the diffractive optical element with the focused electromagnetic radiation, the electromagnetic radiation incident on the optical waveguide, from the diffractive optical element, being sufficiently intense to cause the permanent change in the index of refraction in the core of the optical waveguide.

Fiber Bragg grating sensor in polymer-coated ultra-thin optical fibers and method for producing same

A solution is provided comprising boron nitride nanotubes (BNNTs) in a liquid solvent. An optical waveguide, such as an optical fiber, is contacted with the solution so as to form a layer of the solution supported on at least a portion of the optical waveguide. The liquid solvent is then removed from the layer of the solution supported on the optical waveguide in order to form a coating of the BNNTs on the optical waveguide. Further provided is a BNNT coated optical waveguide for use as a sensor.

Boron nitride nanotube coated optical waveguide and uses thereof

Provided is an optical waveguide with an inscribed Bragg grating, where the Bragg grating is stable at high temperature, has low scattering loss and high reflectivity. Also provided is a method for inscribing a Bragg grating in an optical waveguide, the method comprising irradiating the optical waveguide with electromagnetic radiation from an ultrashort pulse duration laser of sufficient intensity to cause a permanent change in an index of refraction within a core of the optical waveguide, where the irradiating step is terminated prior to erasure of a Bragg resonance, and heating the optical waveguide to a temperature and for a duration sufficient to substantially remove a non-permanent grating formed in the optical waveguide by the irradiating step.

Low insertion loss high temperature stable fiber Bragg grating sensor and method for producing same

There is provided an alignment system and method for use in an ultrashort pulse duration laser-based Fiber Bragg Grating (FBG) writing system, the alignment system comprising: clamps configured to hold a coated optical fiber in a position perpendicular to a beam path of an ultrashort pulse duration laser-based FBG writing station; an optical detector; and a control system with an input from the optical detector and an output to adjust parameters of an optical source and the FBG writing station adjust a distance between the optical fiber and an optical source of the writing station based on luminescence generated in a core of the optical fiber as indicated in a signal received at the input from the optical detector.

Automated system for trans-jacket fibre Bragg grating inscription and manufacturing

An apparatus for use with a pulsed laser source for forming an optical grating in a target includes an adjustable telescope having an element with a negative optical power, for generation of a diverging optical beam, so that the optical beam has adjustable divergence upon exiting the telescope while focusing of light inside the telescope is avoided. A transmission diffraction grating is disposed in the optical beam exiting the telescope, for forming an optical interference pattern on the target. Optical gratings with different grating periods may be formed by adjusting the divergence of the optical beam exiting the telescope. Lack of tight focal spots inside the telescope enables use of ultrashort pulse duration, high peak intensity laser sources.

Forming an optical grating with an apparatus providing an adjustable interference pattern

A filter and a method of filtering a high frequency electrical signal using photonic components is disclosed. The filter has a serially fiber-coupled laser source, a modulator, a filter, and a photodetector. The electrical signal is applied to the modulator. The modulated light propagates through the filter which is constructed to pass not only a modulated sideband, but also at least a fraction of light at the carrier frequency of the laser. The photodetector detects a signal at the beat frequency between the carrier and sideband signals, after both signals have propagated through the filter. As a result, a separate optical branch for light at the carrier frequency is not required, which considerably simplifies the filter construction and makes it more stable and reliable.

Photonic filtering of electrical signals

A dual parameter sensor for sensing temperature and mechanical or chemical or related information is disclosed. The sensor is formed of an optical waveguide suitable for use in-situ in a high temperature environment having a Bragg grating written into a core region thereof with short-pulsed electromagnetic radiation. By noting the thermal Black Body radiation level above 650&#xb0; C., wavelength shifts due to temperature can be decoupled from wavelength shifts due to the other parameter being sensed. Advantageously the thermal radiation can be used as an optical source to probe the Bragg grating, considerably simplifying the interrogating apparatus, removing the need for an extrinsic optical source to probe the sensor.

Method and system for measuring a parameter in a high temperature environment using an optical sensor

A method of producing a thermally stable grating allows the grating to be placed in environments where temperatures reach 1000&#xb0; C. These gratings may be concatenated so as to form a sensor array. The method requires a step of lowering the characteristic intensity threshold of a waveguide by at least 25%, followed by irradiating the waveguide with femtosecond pulses of light having a sufficient intensity and for a sufficient duration to write the grating so that at least 60% of the grating remains after exposures of at least 10 hours at a temperature of at least 1000&#xb0; C. Pre-writing a Type I grating before writing a minimal damage Type II grating lowers the characteristic threshold of the waveguide so that a stable low damage type II grating can be written; alternatively providing a hydrogen or deuterium loaded waveguide before writing the grating lowers the characteristic threshold of the waveguide.

High temperature stable fiber grating sensor and method for producing same

A method of producing a thermally stable grating allows the grating to be placed in environments where temperatures reach 1000&#xb0; C. and where the grating is relatively stable and has very low loss from scatter. These gratings have spectral characteristics that allow them to be concatenated so as to form a sensor array. The method requires a step of lowering the characteristic intensity threshold of a waveguide by at least 25%, followed by irradiating the waveguide with femtosecond pulses of light having a sufficient intensity and for a sufficient duration to write the grating so that at least 60% of the grating remains after exposures of at least 10 hours at a temperature of at least 1000&#xb0; C. Pre-writing a Type I grating before writing a minimal damage Type II grating lowers the characteristic threshold of the waveguide so that a stable low damage type II grating can be written; alternatively providing a hydrogen or deuterium loaded waveguide before writing the grating lowers the characteristic threshold of the waveguide.

A method of inducing birefringence in an optical waveguide is disclosed wherein the waveguide cladding is irradiated with energy of a sufficient intensity so as to induce a stress in the optical waveguide so as to cause a multitude of spaced stress induced regions within the cladding of the optical waveguide such that there are 10 to 5000 spaced regions per mm and wherein the stress induced regions are proximate the core greater than 2 microns distance from the core-cladding interface. This waveguide has numerous uses, for example a fiber sensor.

Method of changing the birefringence of an optical waveguide by laser modification of the cladding

A device for providing an expanded mode field from a single mode optical waveguide is formed by fusing a length of single mode optical fiber with a length of fiber rod absent a cladding and adiabatically tapering the fused region. The length of single mode fiber has a core having a refractive index nand a cladding having a refractive index n, wherein n&#x3c;nand wherein the cladding has an outer diameter &#x3c1;. The length of fiber rod absent the cladding has a refractive index of the fiber rod is substantially the same as the cladding index nof the single mode optical fiber. The outer diameter of the length of fiber rod is &#x3c1;, the same as the cladding diameter of the single mode fiber.

Optical fiber fundamental mode field expander

An optical sensor for sensing information relating to an analyte liquid or gas, has a a planar substrate having a refractive index n. The planar substrate supports a ridge waveguide having an unclad top portion having a refractive index n. The substrate serves as cladding layer for the ridge waveguide at a location where the ridge waveguide contacts the substrate. A Bragg grating inscribed in the ridge waveguide has two modes for providing information relating to both temperature and refractive index of the surrounding analyte liquid or gas. A cladding mode has a different response to the analyte when compared to a Bragg resonance response. Both modes have a same reaction to temperature, wherein said Bragg grating is formed within the unclad region of ridge waveguide, wherein n&#x3c;n. Advantageously multiple parameters can be sensed using only a single Bragg grating.

Ridge waveguide optical sensor incorporating a Bragg grating

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Ottawa, Canada

Stephen J Mihailov