Abstract: A multi-channel mode converter includes a lens array having a first lens and a second lens, a glass block coupled to the lens array, and a fiber assembly unit (FAU) array coupled to the glass block, the FAU array including a first fiber corresponding to the first lens, and a second fiber corresponding to the second lens. The FAU array provides for a corresponding number of fibers and lenses such that a specific single fiber corresponds to a specific single lens, there being a 1:1 relationship between fibers and lenses. A mode converter system comprises: a lens array comprising: a first silicon lens configured to convert a first mode between a first waveguide and a first fiber, and a second silicon lens configured to convert a second mode between a second waveguide and a second fiber, and a glass block coupled to the lens array and configured to provide an optical path for a first light beam corresponding to the first silicon lens and a second light beam corresponding to the second silicon lens.

Abstract: A multi-channel mode converter includes a lens array having a first lens and a second lens, a glass block coupled to the lens array, and a fiber assembly unit (FAU) array coupled to the glass block, the FAU array including a first fiber corresponding to the first lens, and a second fiber corresponding to the second lens. The FAU array provides for a corresponding number of fibers and lenses such that a specific single fiber corresponds to a specific single lens, there being a 1:1 relationship between fibers and lenses. A mode converter system comprises: a lens array comprising: a first silicon lens configured to convert a first mode between a first waveguide and a first fiber, and a second silicon lens configured to convert a second mode between a second waveguide and a second fiber, and a glass block coupled to the lens array and configured to provide an optical path for a first light beam corresponding to the first silicon lens and a second light beam corresponding to the second silicon lens.

Abstract: A wavelength tunable laser includes: a heating layer, a dielectric layer, reflectors, a transport layer, a support layer, and a substrate layer. The heating layer is located above the transport layer; the transport layer is located above the support layer, and the transport layer includes an upper cladding layer, a waveguide layer, and a lower cladding layer from top to bottom; the reflector is located in the transport layer; the support layer has a protection structure, where the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure has a support structure; and the substrate layer is located below the support layer. The heating layer, the reflector, and a part of the transport layer form a suspended structure to prevent heat dissipation. Thus thermal tuning efficiency can be improved, and power consumption can be lowered.

Abstract: An integrated coherent receiver that is configured to receive an optical signal and receive a local oscillator (LO) source from a remote location. The integrated coherent receiver is configured to extract phase and frequency information carried by the optical signal using the LO source from the remote location.

Abstract: An all-optical network comprises: a first network; a second network; and a PWXC coupling the first network to the second network and comprising passive optical components. A method comprises: receiving a first optical signal from a first tail node of a first network; directing the first optical signal from a first input port of a PWXC to a first output port of the PWXC using first passive optical components; and transmitting the first optical signal to a third head node of a third network. An all-optical network comprising: a light bank; a first network coupled to the light bank; a second network coupled to the light bank; and a first PWXC coupling the first network and the second network.

Abstract: A tunable laser is provided, including a first reflector, a second reflector, a phase adjustment area, a gain area, a first detector, a second detector, and a controller. The phase adjustment area is located between the first reflector and the gain area, the gain area is located between the phase adjustment area and the second reflector, a reflectivity of the first reflector is adjustable, and a reflectivity of the second reflector is adjustable. The first detector is configured to convert an optical signal of the first reflector into a first electrical signal. The second detector is configured to convert an optical signal of the second reflector into a second electrical signal. The controller is configured to adjust at least one of the reflectivity of the first reflector or the reflectivity of the second reflector based on the first electrical signal and the second electrical signal.

Abstract: A data center includes a wavelength source, a first optical component, a first communications device, and a second communications device. The wavelength source is configured to generate an N-wavelength laser beam. The first port of the first optical component is configured to receive an M-wavelength laser beam from the wavelength source. The second port of the first optical component is configured to send the M-wavelength laser beam to the first communications device. The M-wavelength laser beam includes at least a first-wavelength laser beam. The second port of the first optical component is further configured to receive a modulated first optical signal from the first communications device, the modulated first optical signal is obtained after the first communications device modulates a service signal onto the first-wavelength laser beam. The third port of the first optical component is configured to send the modulated first optical signal to the second communications device.

Abstract: An integrated coherent receiver that is configured to receive an optical signal and receive a local oscillator (LO) source from a remote location. The integrated coherent receiver is configured to extract phase and frequency information carried by the optical signal using the LO source from the remote location.

Abstract: A data center includes a wavelength source, a first optical component, a first communications device, and a second communications device. The wavelength source is configured to generate an N-wavelength laser beam. The first port of the first optical component is configured to receive an M-wavelength laser beam from the wavelength source. The second port of the first optical component is configured to send the M-wavelength laser beam to the first communications device. The M-wavelength laser beam includes at least a first-wavelength laser beam. The second port of the first optical component is further configured to receive a modulated first optical signal from the first communications device, the modulated first optical signal is obtained after the first communications device modulates a service signal onto the first-wavelength laser beam. The third port of the first optical component is configured to send the modulated first optical signal to the second communications device.

Abstract: An all-optical network comprises: a first network; a second network; and a PWXC coupling the first network to the second network and comprising passive optical components. A method comprises: receiving a first optical signal from a first tail node of a first network; directing the first optical signal from a first input port of a PWXC to a first output port of the PWXC using first passive optical components; and transmitting the first optical signal to a third head node of a third network. An all-optical network comprising: a light bank; a first network coupled to the light bank; a second network coupled to the light bank; and a first PWXC coupling the first network and the second network.

Abstract: A dense wavelength-division multiplexing (DWDM) optical network includes an optical input port configured to receive unmodulated optical signals from the optical fiber comprising wavelength channels; one or more modulators coupled to the optical input port wherein the one or more modulators are each configured to modulate a respective first wavelength channel of the wavelength channels with respective data to produce a modulated first wavelength channel when the modulator is in a transmit state; wherein an input optical power of each modulator is kept at substantially a first level and an output optical power of the each modulator is kept at substantially a second level during operation of the modulator. A method and an optical network node are also disclosed therein.

Abstract: A wavelength tunable laser includes: a heating layer, a dielectric layer, reflectors, a transport layer, a support layer, and a substrate layer. The heating layer is located above the transport layer; the transport layer is located above the support layer, and the transport layer includes an upper cladding layer, a waveguide layer, and a lower cladding layer from top to bottom; the reflector is located in the transport layer; the support layer has a protection structure, where the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure has a support structure; and the substrate layer is located below the support layer. The heating layer, the reflector, and a part of the transport layer form a suspended structure to prevent heat dissipation. Thus thermal tuning efficiency can be improved, and power consumption can be lowered.

Abstract: A tunable laser is provided, including a first reflector, a second reflector, a phase adjustment area, a gain area, a first detector, a second detector, and a controller. The phase adjustment area is located between the first reflector and the gain area, the gain area is located between the phase adjustment area and the second reflector, a reflectivity of the first reflector is adjustable, and a reflectivity of the second reflector is adjustable. The first detector is configured to convert an optical signal of the first reflector into a first electrical signal. The second detector is configured to convert an optical signal of the second reflector into a second electrical signal. The controller is configured to adjust at least one of the reflectivity of the first reflector or the reflectivity of the second reflector based on the first electrical signal and the second electrical signal.

Abstract: Methods, apparatus, and systems are provided including an electro-absorption modulator (EAM) with local temperature control for optical communication. One aspect provides an optical EAM including a semiconductor portion configured to modulate light for transmission or reception of an optical signal. The modulator includes a temperature sensing element configured to sense temperature and to provide an output signal based on the sensed temperature, and a temperature control element configured to control temperature of the semiconductor portion based on the output signal from the temperature sensing element. In one example, the semiconductor portion includes germanium silicon (GeSi).

Abstract: Methods, apparatus, and systems are provided including an electro-absorption modulator (EAM) with local temperature control for optical communication. One aspect provides an optical EAM including a semiconductor portion configured to modulate light for transmission or reception of an optical signal. The modulator includes a temperature sensing element configured to sense temperature and to provide an output signal based on the sensed temperature, and a temperature control element configured to control temperature of the semiconductor portion based on the output signal from the temperature sensing element. In one example, the semiconductor portion includes germanium silicon (GeSi).

Abstract: A dense wavelength-division multiplexing (DWDM) optical network comprises an optical bus, which includes an optical source configured to generate a plurality of unmodulated optical signals each having a different wavelength; an optical multiplexer configured to multiplex the unmodulated optical signals to produce a combined, unmodulated optical signal, and to transmit the combined, unmodulated optical signal through an optical fiber; a plurality of nodes connected in sequence to the output of the optical multiplexer. The plurality of nodes are connected by the optical fiber. A DWDM optical network and a method of operation of the DWDM optical network are also disclosed therein.

Abstract: A dense wavelength-division multiplexing (DWDM) optical network includes an optical input port configured to receive unmodulated optical signals from the optical fiber comprising wavelength channels; one or more modulators coupled to the optical input port wherein the one or more modulators are each configured to modulate a respective first wavelength channel of the wavelength channels with respective data to produce a modulated first wavelength channel when the modulator is in a transmit state; wherein an input optical power of each modulator is kept at substantially a first level and an output optical power of the each modulator is kept at substantially a second level during operation of the modulator. A method and an optical network node are also disclosed therein.

Abstract: A method includes forming a first optical structure with an inverse taper and a separate optical structure on a semiconductor chip. The illustrative method also includes applying a protective structure over the optical structures and patterning the protective structure to expose the separate optical structure. The method further includes removing a portion of the separate optical structure to form a separate trimmed taper separate from, but adjacent to, the first optical structure. The protective structure is then removed from the first optical structure. Apparatuses are also disclosed.

Abstract: An apparatus includes a first waveguide configured to receive an input signal. A section of the first waveguide has a length between a first initial point and a first end point. A first polarization rotator is located within the section at a first distance from the first initial point of the section of the first waveguide. A section of a second waveguide is configured to receive the input signal, and has the same length between the second initial point and a second end point. A second polarization rotator is located within the section of the second waveguide at a second distance from the second initial point of the section of the second waveguide. More particularly, a relative distance between the first distance and the second distance is configured to achieve a desired phase delay of an output signal from the first waveguide and an output signal from the second waveguide.

Abstract: An apparatus includes a first waveguide configured to receive an input signal. A section of the first waveguide has a length between a first initial point and a first end point. A first polarization rotator is located within the section at a first distance from the first initial point of the section of the first waveguide. A section of a second waveguide is configured to receive the input signal, and has the same length between the second initial point and a second end point. A second polarization rotator is located within the section of the second waveguide at a second distance from the second initial point of the section of the second waveguide. More particularly, a relative distance between the first distance and the second distance is configured to achieve a desired phase delay of an output signal from the first waveguide and an output signal from the second waveguide.