Abstract:
An embodiment of an apparatus includes an optical fiber for which a complete orthogonal basis of propagating modes at an optical telecommunication frequency includes ones of the propagating modes with different angular momenta. The optical fiber has a tubular optical core and an outer optical cladding in contact with and surrounding the tubular optical core. The tubular optical core has a larger refractive index than the optical cladding. The tubular optical core is configured such that those of the propagating modes whose angular momenta have the lowest magnitude for the propagating modes have substantially the same radial intensity profile.
Abstract:
An apparatus includes one or more optical de-interleavers. Each optical de-interleaver includes an optical component having a first pair of optical input and output ports and a second pair of optical input and output ports and a 1×2 optical coupler. Each optical output port of the optical component is optically connected to a corresponding optical port of the 1×2 optical coupler. The optical component is constructed to operate as a first optical filter for light propagating between the optical ports of the first pair and is constructed to operate as a second optical filter for light propagating between the optical ports of the second pair. The first and second optical filters have substantially regularly spaced and interleaved passbands.
Abstract:
Provided is an apparatus and method for manufacture thereof. The apparatus includes a passive optical waveguide structure and a photodiode detector structure. The structures are located on a substrate, and the photodiode detector is laterally proximate to the semiconductor passive waveguide structure. The passive optical waveguide structure includes a first lateral portion of a semiconductor optical core layer on the substrate, a semiconductor upper optical cladding layer on the optical core layer, and a first lateral portion of a doped semiconductor layer on the upper optical cladding layer. The photodiode detector structure includes a second lateral portion of the semiconductor optical core layer, a semiconductor optical absorber layer on the optical core layer, and a second lateral portion of the doped semiconductor layer.
Abstract:
A mode-locked laser that has an optical cavity containing multiple optical amplifiers, each dedicated to a respective spectral portion of an optical signal generated by the laser, wherein the dispersion effects are managed by utilizing a separate intra-cavity phase tuner for each such spectral portion and/or by having appropriately configured waveguides corresponding to different spectral portions. Advantageously, a relatively wide combined gain spectrum provided by the optical amplifiers and the intra-cavity dispersion compensation provided by the phase tuners and/or waveguides enable this laser to realize a mode-locking regime that results in the emission of an optical pulse train having a relatively wide frequency spectrum. In one embodiment, the optical cavity of the mode-locked laser has a perfectly spectrally sampled arrayed waveguide grating (AWG) that is configured to divide the optical signal into the spectral portions and apply these portions to the respective waveguides, optical amplifiers, and phase tuners.
Abstract:
Provided is an apparatus and method for use thereof. The apparatus, in one embodiment, includes first and second 1×N couplers integrated on a substrate and configured to receive an optical symbol having an intended time slot, N being at least three. The apparatus, in this embodiment, further includes N waveguide arms integrated on the substrate, having modulators and coupled between the first and second 1×N couplers. The apparatus, in this embodiment, additionally, includes a modulator controller configured to drive the modulators such that, following transmission over a distance, components of the optical symbol outside of the intended time slot are attenuated relative to components within the intended time slot.
Abstract:
An exemplary optical modulator includes an interferometer. The interferometer includes an input optical coupler, an output optical coupler, and two or more controllable optical waveguides. Each controllable optical waveguide connects the input optical coupler to the output optical coupler and has an electro-absorption modulator along a segment thereof. Two of the controllable optical waveguides are connected to transmit to an output of the output optical coupler light of substantially different maximum amplitude.
Abstract:
An apparatus comprising a planar optical waveguide having an optical core and optical cladding next to the optical core. The optical core or cladding includes a plurality of particles therein. Each particle has a nucleus and polymeric molecules permanently bonded to the nucleus to form a shell. A plurality of nuclei are dispersed in said core or cladding.
Abstract:
A novel design for an optical differential quadrature phase shift keying (DQPSK) modulator comprises two intensity modulators in a three-arm interferometer.
Abstract:
A reconfigurable optical add/drop multiplexer (ROADM) includes a first optical dynamic gain equalization filter (DGEF) having a first input for receiving an initial wavelength division multiplexed (WDM) signal, a first output for sending a phase shifted WDM signal, and a second output connected to a demultiplexer for demultiplexing a WDM drop signal thereby producing a plurality of drop channels. A second DGEF having a first input for receiving the phase shifted WDM signal, a second input connected to a multiplexer, for multiplexing a plurality of add channels to produce thereby a wavelength division multiplexed (WDM) add signal, and an output for sending a second adjusted WDM signal. The ROADM allows for the channels from the initial WDM signal to be dropped, added and equalized.
Abstract:
A method and apparatus for mitigating intersymbol interference (ISI) from narrow-band optical filtering and improving transmission performance by filtering multichannel optical signals using an optical filter device that exhibits a desired loss ripple in the transmittance profile of the filter passband.