The invention relates to a nanocomposite material. The nanocomposite material comprises a matrix material and a plurality of quantum dots dispersed in the matrix material. The nanocomposite material has a nonlinear index of refraction γ that is at least 10 −9 cm 2 /W when irradiated with light having a wavelength λ between approximately 3×10 −5 cm and 2×10 −4 cm.

Nanocomposite materials with engineered properties

The invention relates to a quantum dot The quantum dot comprises a core including a semiconductor material Y selected from the group consisting of Si and Ge The quantum dot also comprises a shell surrounding the core The quantum dot is substantially defect free such that the quantum dot exhibits photoluminescence with a quantum efficiency that is greater than 10 percent

Quantum dots of Group IV semiconductor materials

The invention relates to an optical device. The optical device comprises a waveguide core and a nanocomposite material optically coupled to the waveguide core. The nanocomposite material includes a plurality of quantum dots. The nanocomposite material has a nonlinear index of refraction γ that is at least 10 −9 cm 2 /W when irradiated with an activation light having a wavelength λ between approximately 3×10 −5 cm and 2×10 −4 cm.

Optical devices with engineered nonlinear nanocomposite materials

An optical communications system and method, the system comprising: a multimodal optical waveguide (3) through which light waves are propagated, which comprises a core (3a) and a cladding (3b) surrounding the core; at least one launching apparatus (5) for selectively launching waves of a plurality of different modes m or modal groups in the waveguide (3); and at least one detecting apparatus (7) for detecting waves of a plurality of different modes m or modal groups in the waveguide (3); whereby the launching apparatus (5) is operative as a multiplexer for selectively launching waves of a plurality of different modes m or modal groups in the waveguide (3) and the detecting apparatus (7) is operative as a de-multiplexer for de-multiplexing light from a plurality of separate modes m or modal groups in the waveguide (3), and the optical system, through operation of the launching apparatus (5) and the detecting apparatus (7), provides for multiplexed communication over the waveguide (3).

Mode-selective launching and/or detecting in an optical waveguide

An optical fibre arrangement has at least two optical fibre sections, each optical fibre section defining an outside longitudinally extending surface. The outside longitudinally extending surfaces are in optical contact with each other. The invention further provides for an amplifying optical device have an optical fibre arrangement as just described, and a pump source. The amplifying optical device is configured such that the pump source illuminates the amplifying optical fibre. A amplifying arrangement is also disclosed. The amplifying arrangement includes a plurality of amplifying optical devices as just described, and each amplifier also has at least one input fibre and a first multiplexer connected to the input fibre. Each amplifier is configured such that at least one of the amplifying optical fibres is connected to the first multiplexer. The amplifying arrangement also has a second multiplexer connected to each of the first multiplexers.

Multi-fibre arrangement for high power fibre lasers and amplifiers

An optical channel waveguide amplifier and fabrication process are provided for an optical communications system. The amplifier employs an optical waveguide having a core (12) of active material exhibiting optical fluorescence when stimulated. The core has a propagation axis extending from an input surface to an output surface. The input surface intersects the propagation axis at a non-orthogonal angle (e.g, 45°). A cladding (14) at least partially surrounds the core, and a coating is provided over the angled input surface of the core. The coating (20) is anti-reflective of the optical signal, input at a predetermined signal wavelength, and is highly reflective of the pump, input at a predetermined pump wavelength. A prism (30), index-matched to the core, is secured to the angled face of the optical waveguide so that the input signal may be focused into the core through the prism and the coating collinearly with the axis of propagation, while the pump is reflected into the core off the coating at the angled input surface from an angle to the axis of propagation. The optical signal undergoes amplification within the core by stimulated emissions of the active material driven by the pump.

Optical channel waveguide amplifier

A side-polished fiber/overlay waveguide architecture and process for non-invasively implementing an optical amplifier are provided for an optical communications system. A "channel" overlay waveguide is employed to constrain for amplification optical energy evanescently coupled to the overlay waveguide from the side-polished optical fiber. One of two amplification methods can be employed. The first involves inducing stimulated emission with the overlay waveguide and the second uses a second order, non-linear frequency conversion to down-convert a high-power, short-wavelength pump signal into the waveguide to amplify the optical energy coupled thereto. Amplification of optical energy in the channel overlay waveguide can be established within a single beat length of evanescent removal to evanescent return of the optical energy to the side-polished fiber optic.

Optical amplifier and process for amplifying an optical signal propagating in a fiber optic employing an overlay waveguide and stimulated emission

A compound waveguide device (10) having a channel waveguide (60) in optical proximity to an elongate waveguide (30) propagating an optical signal therein is disclosed. The channel waveguide (60) includes a coupling surface through which optical energy is evanescently coupled to or from the optical signal propagating in the elongate waveguide (30). The channel waveguide (60) is shaped to confine distribution of the optical energy therein along axes transverse to the axis of propagation of the optical energy. Transverse diffraction of the optical energy within the channel waveguide (60) is thereby limited. In one embodiment, the elongate waveguide (30) is a side-polished fiber optic waveguide. Electro-optic control of the compound waveguide is disclosed, as are bandstop, bandpass and detection configurations thereof.

Compound optical waveguide and filter applications thereof

A method in which a separate preformed optical material is suitably sized for easy handling, manipulation, and fabrication into a waveguide having a core (formed from the optical material) having transverse cross-sectional dimensions on the order of only tens of microns. The method may include a plurality of mechanical steps, e.g., lapping, polishing, and/or dicing, and bonding steps, e.g., attaching with adhesives. In one embodiment, the method includes the steps of providing an optical material, thinning and polishing the optical material to form a core comprising a plurality of longitudinally extending surfaces, providing a plurality of support substrates, and attaching the plurality of support substrates to the longitudinally extending surfaces of the core. The plurality of support substrates may be attached to the plurality of longitudinally extending surfaces of the optical material with an adhesive. The optical material may include a high refractive index, and the plurality of support substrates and/or the adhesive may include a low refractive index.

Method for fabricating an optical waveguide

A side-polished fiber/overlay waveguide architecture and process for non-invasively implementing an optical amplifier are provided for an optical communications system. A "channel" overlay waveguide is employed to constrain for amplification optical energy evanescently coupled to the overlay waveguide from the side-polished optical fiber. The overlay waveguide exhibits a non-linear response of second order, and non-linear frequency conversion is employed to down-convert a high-power, short-wavelength pump signal into the waveguide to amplify the optical energy coupled thereto. The channel overlay waveguide is dimensioned to allow for phase matching between highest order modes of the optical signal within the side-polished fiber optic and the pump signal provided to the channel overlay waveguide. A low-index matching layer is disposed between the channel overlay waveguide and the side-polished fiber optic to facilitate phase matching of the propagation modes. Amplification of optical energy in the channel overlay waveguide is established within a single beat length of evanescent removal to evanescent return of the optical energy to the side-polished fiber optic.

Brian L. Lawrence

Papers

Optical channel waveguide amplifier

Optical amplifier and process for amplifying an optical signal propagating in a fiber optic employing an overlay waveguide and stimulated emission

Compound optical waveguide and filter applications thereof

Method for fabricating an optical waveguide

Optical amplifier and process for amplifying an optical signal propagating in a fiber optic