Google Inc.

Pirelli Cavi E Sistemi S.p.a.

Mosaid Technologies Corporation

Other

Pirelli & C. S. P. A.

Consorzio Nazionale Interuniversitario Per Le Telecomunicazioni (cnit)

Pirelli Tyre S.p.a.

Pgt Photonics, S.p.a

Luciano Socci

Marco Romagnoli

Silvia Ghidini

Paola Galli

Lorenzo Bolla

Giacomo Gorni

Giorgio Grasso

Pierluigi Franco

Raffaele Corsini

Marco Piazza

Francesco Maria Tassone

Michele Midrio

Daniele Garbelli

Gaia Cevini

Stefano Lorenzotti

Fabrizio Carbone

Marc Romagnoli

Federico Boffi

In an integrated polarization splitting and rotating photonic device comprising at least one first waveguide; a second waveguide, both said waveguides extending from an input section to an output section; a top cladding; a bottom cladding and a symmetry-breaking layer so as to form an optical guiding structure in a wafer chip, said top and bottom claddings extending throughout the whole optical guiding structure sandwiching said waveguides therebetween, said symmetry-breaking layer extends in the optical guiding structure at least over the whole guiding structure length, and, at the input section, the at least one first waveguide core has a predetermined width through the optical guiding structure to the output section, receiving an input light signal, and further, the second waveguide core, both at the input and the output section, has a width narrower than said predetermined width of the first waveguide core; so that the optical guiding structure guides a first mode substantially confined within said at least one first waveguide core and a second mode substantially confined within said second semiconductor waveguide core said first and said second modes having the same polarization at the output section.

Integrated photonic polarisation rotator and splitter and related method

An optical device includes an optical splitter having an input port, a first output port and a second output port and is adapted to receive at said input port a WDM optical signal including a plurality of channels equally spaced by a frequency spacing and occupying an optical bandwidth, and wherein the optical splitter is adapted to output at the first and second output ports, respectively, a first and a second portion of the optical signal; an optical combiner having a respective first and second input ports and a respective output port; a first optical path optically connecting the first output port of the optical splitter to the first input port of the optical combiner; a second optical path optically connecting the second output port of the optical splitter to the second input port of the optical combiner, a first optical filter optically coupled along the first optical path, and a second optical filter optically coupled to the second optical path and the free spectral range of both the first and the second optical filter is equal to an odd multiple of the frequency spacing and greater than half of the optical bandwidth.

Method and system for tunable optical filtering

The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a frequency spacing and occupying an optical bandwidth, comprises: a) operating an optical filter comprising a plurality of resonators, wherein a first resonator of the plurality is optically coupled to the optical signal and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz; b) operating the optical filter so as to obtain a separation between said respective resonance of at least one resonator with respect to said respective resonance of at least another different resonator, the separation being greater than or equal to 25 GHz; c) operating the optical filter so that said respective resonance of each one of the plurality of resonators falls within a second frequency band, different from the first frequency band, having bandwidth less than or equal to 15 GHz, wherein during the procedure from step a) to step c), at least one among said respective resonance of the at least one resonator and said respective resonance of the at least another different resonator is moved also outside a frequency region spanning between, and including, the first and the second frequency band. A corresponding device for filtering an optical signal is disclosed.

Method and device for hitless tunable optical filtering

A method of filtering an optical signal includes operating an optical filter having resonators, each having a respective free spectral range and a respective resonance falling within a first frequency band, first tuning at least one resonator with respect to at least another resonator to obtain a separation between any resonance of at least one resonator falling within an optical bandwidth with respect to a resonance of at least another resonator nearest to the any resonance, second tuning all the resonators of the optical filter so as to move all respective resonances by a respective frequency interval greater than a frequency spacing, and third tuning the at least one resonator and the at least another resonator such that a further respective resonance of each one of the resonators falls within a second frequency band, different from the first frequency band.

An optical mode transformer comprises a first waveguide including a first core, a first cladding and an end facet configured to be coupled to an optical fiber. A second waveguide comprises a second core and a second cladding, and is arranged with respect to the first waveguide so as to realize an evanescent optical coupling with the first waveguide. The second core comprises a tapered region, in at least a portion of which the evanescent coupling takes place. The first core and the second core are separated by a gap. A first refractive index contrast of the first waveguide is less than a second refractive index contrast of the second waveguide.

Optical mode transformer, in particular for coupling an optical fiber and a high-index contrast waveguide

An optical mode transformer comprises a first waveguide including a first core, a first cladding and an end facet configured to be coupled to an optical fiber. The transformer further includes a second waveguide comprising a second core, a second cladding and an end directly coupled to an end of the first waveguide. A third waveguide comprises a third core and a third cladding, and is arranged with respect to the second waveguide so as to realize an evanescent optical coupling with the second waveguide. The third core includes a tapered region wherein evanescent coupling takes place, and wherein a refractive index contrast of the first waveguide is less than a refractive index contrast of the second waveguide, the refractive index contrast of the second waveguide is less than a refractive index contrast of the third waveguide, and the refractive index contrast of the third waveguide is not less than 18%.

An optical device includes an optical splitter having an input port, a first output port, a second output port and a resonant structure including at least a resonator, the optical splitter being adapted to receive at the input port a WDM optical signal and to output at the first and second output ports, respectively, a first and a second portion of the optical signal, the second portion including the channels lying on a sub-grid of optical frequencies spaced by an integer multiple of the WDM frequency spacing; an optical combiner having a first input port, a second input port, an output port and adapted to receive at the first and second input ports, respectively, the first and the second portions and adapted to output them at said output port; a first optical path optically connecting the first output port of the optical splitter to the first input port of the optical combiner so as to propagate the first portion; a second optical path optically connecting the second output port of the optical splitter to the second input port of the optical combiner so as to propagate the second portion; and an optical filter optically coupled to the second optical path, wherein the optical combiner includes at least one resonant structure including at least a resonator.

Method and device for tunable optical filtering

A method for switching from a first optical path optically coupled to an optical processing device to a second optical path, the first and second optical paths optically connecting, in parallel configuration, a first optical switch to a second optical switch, according to the following steps: directing optical radiation comprising at least a fast operating wavelength through the first optical path to the optical processing device, which is tuned to the first operating wavelength; tuning a resonant all-pass filter optically coupled to the second optical path so as to match, at least at a wavelength adjacent to the first operating wavelength, a phase distortion introduced by the optical processing device on the optical radiation; synchronously actuating the first and the second optical switch so as to switch the optical radiation from the first optical path to the second optical path.

Method and system for hitless tunable optical processing

Bidirectional isolating devices including non-reciprocal rotators (i.e. Faraday rotators) and wavelength selective reciprocal polarization rotators are disclosed. Each wavelength selective rotator behaves like a half-wave retarder in a first frequency range and behaves like a full-wave retarder in a second frequency range, according to a substantially periodic transfer function. The rotation has a predetermined number of birefringent elements (e.g. waveplates), the thickness and the orientation of which are chosen so as to obtain a transition between the half-wave retarder behavior and the full-wave retarder behavior in a frequency range lower than or equal to 40% of the period of the transfer function. In order to satisfy such a requirement, a relatively high number of birefringent elements is required, i.e. at least the five birefringent elements. Advantageously, the isolating device may comply with any allocation scheme for the opposite propagating signals.

Optical devices comprising series of birefringent waveplates

A WDM system includes a transmission station, a receiving station, a first optical path and a second optical path. The first optical path includes a first section and a second section, the second section being capable of compensating at least partially the dispersion accumulated by a series of optical channels along the first section. The series of channels includes at least a first plurality of channels having an average dispersion of the same sign in the first optical path. The system also includes at least a first conversion device, capable of inverting the spectrum and modifying the wavelength of at least the first plurality of channels, to produce a second plurality of channels having an average chromatic dispersion of the same sign in the second optical path.

Wavelength division multiplexing optical transmission system using a spectral inversion device

A compensating optical fiber length having a negative chromatic dispersion slope, the compensating optical fiber having a core region surrounded by a cladding region, the cladding region defining a first ring of holes, which substantially defines, around the core region an annulus with an inner radius rand an outer radius r, and at least one second ring of holes that surrounds the first ring of holes, the holes running along the compensating optical fiber longitudinally and being spaced apart from each other substantially according to a predefined pitch &#x39b;, wherein a) r&#x2266;&#x3bb;/n&#x2266;rwhere n is the refractive index of the material making up the core region of the compensating optical fiber length; b) the holes of the first and the at least one second ring are substantially of the same diameter d; and c) the ratio d/&#x39b; substantially satisfies the following relationship (A) 0.8&#x2266;d/&#x39b;&#x3c;1.

Device for the compensation of chromatic dispersion

Device for performing a parametric process, comprising a substantially periodic photonic crystal structure comprising a plurality of unitary cells each comprising

Parametric device for wavelength conversion

Unit ( ) comprising a portion of holey optical fibre ( ) having a length Lc comprising a core region ( ) and a cladding region ( ), said cladding region ( ) comprising, in turn, a plurality of holes passing through it longitudinally, said holes having a respective diameter and being spaced, two by two, according to a respective pitch, said unit comprising also a temperature adjusting device ( ) for bringing and maintaining the holey optical fibre ( ) at temperature values T selectable in a predetermined interval of temperatures Tx-Ty.

Growing community of inventors

Milan, Italy

Luciano Socci