Abstract: A novel phase shifter design for carrier depletion based silicon modulators, based on an experimentally validated model, is described. It is believed that the heretofore neglected effect of incomplete ionization will have a significant impact on ultra-responsive phase shifters. A low V?L product of 0.3 V·cm associated with a low propagation loss of 20 dB/cm is expected to be observed. The phase shifter is based on overlapping implantation steps, where the doses and energies are carefully chosen to utilize counter-doping to produce an S-shaped junction. This junction has a particularly attractive V?L figure of merit, while simultaneously achieving attractively low capacitance and optical loss. This improvement will enable significantly smaller Mach-Zehnder modulators to be constructed that nonetheless would have low drive voltages, with substantial decreases in insertion loss. The described fabrication process is of minimal complexity; in particular, no high-resolution lithographic step is required.

Abstract: Electro-optic modulator includes a substrate, a waveguide formed in a top surface of the substrate, first modulating electrodes and second modulating electrodes. The waveguide includes a Y-shaped incident member, a Y-shaped output member, and first and second connection members. The Y-shaped incident member includes an incident portion, first and second incident branches. The Y-shaped output member includes an output portion, a first and second output branches. The first connection member includes a first branch and a second branch. The second connection member includes a third branch and a fourth branch. The first branch and the second branch are interconnected between the first incident branch and the first output branch and arranged in parallel. The third branch and the fourth branch are interconnected between the second incident branch and the second output branch and arranged in parallel.

Abstract: Optical devices that do not employ magneto-optics materials or non-linear effects to achieve non-reciprocal light propagation. The optical devices are compatible with the fabrication of monolithic photonic integrated circuits such as silicon-on-insulator planar lightwave circuits. In particular the devices use demonstrated passive (beam-splitters, waveguides) and active (phase modulators) components to achieve non-reciprocal light propagation. The devices can be used as non-reciprocal optical modulators or optical isolators when driven by a periodic radio frequency (RF) electric source.

Abstract: An optical hybrid circuit includes an MMI coupler including input channels provided at positions symmetrical first output channels, and second output channels, to convert multilevel modulation signal into first and second optical signals each having an in-phase relationship; first optical coupler coupled to one of the first and the second output channels, and having a branching ratio of 85:15 or 15:85, to convert the first optical signals into third optical signals having a 45- or 135-degree phase relationship; second optical coupler coupled to the other of the first and the second output channels, and having a same branching ratio as that of the first optical coupler, to convert the second optical signals into fourth optical signals having a 135- or 45-degree phase relationship; and a phase controlling region provided on at least one of one of the first output channels and one of the second output channels.

Abstract: An optical modulator that supports a plurality of modulation formats is provided. The optical modulator includes: a distribution part including an optical demultiplexing/variable-branching switchable circuit; an optical modulator array; and an aggregation part including a combining ratio variable combining circuit and/or an optical multiplexing/variable-combining switchable circuit. The distribution part forms any or a combination of a variable 1×M demultiplexer/brancher, a combination of one or more fixed ILFs and an optical switch and a combination of a plurality of variable optical couplers and an optical switch; the optical modulator array includes a plurality of optical modulators; the aggregation part includes a structure of any or a combination of one or more variable optical couplers, a combination of a plurality of variable attenuators, an M×1 variable coupler, a variable M×1 demultiplexer/brancher and a combination of one or more fixed ILFs and an optical switch.

Abstract: An electro-optic modulator includes a substrate, an end-to-end Y-shaped waveguide for optical divergence and convergence, and electrodes. The waveguide is formed in the substrate and the electrodes are formed in the substrate and received voltages act to modulate first and second sections of the waveguide such that the optical output by the first and second sections are equal or opposite to each other in all necessary respects regarding phase and amplitude.

Abstract: An electro-optic modulator includes a substrate, a Y-shaped waveguide, and electrodes. The waveguide is formed in the substrate with diverging and reconverging portions. The electrodes are formed in the substrate to sandwich the diverged portions of the waveguide and receive voltages which modulate each branch of the Y shaped waveguide such that power outputs of branches of the Y shape are precisely synchronized and an improved extinction ratio thus obtained.

Abstract: An electro-optic modulator includes a substrate, an end-to-end Y-shaped waveguide for optical divergence and convergence, and electrodes. The waveguide is formed in the substrate and the electrodes are formed to substantially sandwich the waveguide in the substrate and voltages applied to the electrodes act to modulate first and second sections of the waveguide such that the optical outputs by the first and second sections are equal or opposite to each other in all necessary respects regarding phase and amplitude, and an improved extinction ratio thus obtained.

Abstract: An electro-optic modulator includes a substrate having a polarization inversion region whose polarization is inverted, and a waveguide embedded in the substrate and including a first branch and a second branch. A portion of the first branch is embedded in the polarization inversion region.

Abstract: An electro-optic modulator includes a substrate, a waveguide lens, a Y-shaped waveguide, and electrodes. The waveguide lens and the Y-shaped waveguide are formed in the substrate. The Y-shaped waveguide connects the waveguide lens and includes a first section dedicated for transmitting TE mode and a second section dedicated for transmitting TM mode. The electrodes are configured to modulate outputs of the waveguide lens, the first section, and the second section.

Abstract: A low-voltage optical modulator includes a substrate, a waveguide, a first pair of electrodes, and a second pair of electrodes. The waveguide is diffused into the top surface of the substrate, into a major branch and a parallel modulating branch. A structure of the first and second pair of electrodes are same. The first pair of electrodes includes a first and a second electrode parallel to each other. The first electrode is formed on the modulating branch and the second electrode is opposite to the modulating branch and away from the major branch. The second pair of electrodes includes parallel third and fourth electrodes. The third electrode is formed on the major branch. The fourth electrode is opposite to the major branch and away from the modulating branch.

Abstract: A wavelength selective switch includes a light input and output part in which light input/output ports are arranged in a predetermined direction, the light input/output ports including a first port for inputting light, a second port for outputting the light, and at least one third port for inputting or outputting the light, a wavelength dispersive element optically coupled to the light input and output part, and a phase modulation element which includes a plurality of pixels performing phase modulation and diffractively deflects an optical path of the light arriving from the first port via the wavelength dispersive element by presenting a diffraction-grating-shaped phase modulation pattern, and the light input/output ports are arranged so that a 1st order light of the light is incident on the second port, and the first port and the third port are spaced from an optical axis of a ?1st order light of the light.

Abstract: An electro-optical phase modulator, dual polarization modulator applying that modulator and a phase modulation method are disclosed. A waveguide in an electro-optical substrate has at least two electrodes for modulating the waveguide. Each electrode receives a sequential bit of a precoded digital input and forms a shifting line from a first input end through interaction lengths near the waveguide causing modulation, shifted lengths distal from the waveguide for avoiding modulating the waveguide and transitions between these lengths by shifting the electrode away from or towards the waveguide. At least one electrode has a shorter interaction length closer to the input than a longer interaction length of the same electrode. Each electrode's modulation strength is proportional to its total interaction length, which doubles for each electrode, producing well matched S21 electro-optical responses from 10 kHz to 50 GHz, when shifted to account for the doubling.

Abstract: To provide an optical modulator having a reduced size and reduced power consumption and capable of being easily connected to a waveguide and a method of manufacturing the optical modulator. The optical modulator has at least semiconductor layer (8) having a rib-shaped portion and doped so as to be of a first conduction type, dielectric layer (11) laid on first-conduction-type semiconductor layer (8), and semiconductor layer (9) laid on dielectric layer (11), having the width at the side opposite from dielectric layer (11) increased relative to the width of the rib-shaped portion, and doped so as to be of a second conduction type.

Abstract: Electro-optic modulator includes a substrate, a waveguide formed in a top surface of the substrate, a pair of first modulating electrodes and a pair of second modulating electrodes. The waveguide includes a Y-shaped incident member, a Y-shaped output member, first and second connection members. The Y-shaped incident member includes an incident portion, first and second incident branches. The Y-shaped output member includes an output portion, a first and second output branches. The first connection member includes a first non-modulated branch and a first modulated branch. The second connection member includes a second non-modulated branch and a second modulated branch. The first non-modulated branch and the first modulated branch are interconnected between the first incident branch and the first output branch in parallel. The second non-modulated branch and the second modulated branch are interconnected between the second incident branch and the second output branch in parallel.

Abstract: An optical modulator comprises an input optical splitting unit for bifurcating input light; a final optical coupling unit for coupling optical signals in a polarization state orthogonal to each other; an intermediate optical coupling unit provided in an intermediate position between the input optical splitting unit and the final optical coupling unit; first and second optical paths for connecting the input optical splitting unit and the intermediate optical coupling unit, optical path lengths of the first and second optical paths are approximately equal; third and fourth optical paths for connecting the intermediate optical coupling unit and the final optical coupling unit, optical path lengths of third and fourth optical paths are approximately equal; and three binary phase modulation unit arranged one by one in each of the three optical paths of the first, second, third and fourth optical paths.

Abstract: An optical modulator includes main input and output ports; first and second Mach-Zehnder modulators; a first branching waveguide optically coupling the main input port to the first and second Mach-Zehnder modulators; a first driver circuit connected to the first Mach-Zehnder modulator, the first driver circuit generating a first drive signal having a first amplitude at a first bias point; and a second driver circuit connected to the second Mach-Zehnder modulator, the second driver circuit generating a second drive signal having a second amplitude at a second bias point. The first and second drive signals satisfy at least one of a first condition and a second condition. The first condition is that the first amplitude differs from the second amplitude. The second condition is that the first bias point differs from the second bias point.

Abstract: An optical device comprising a tunable optical frequency comb generator. The comb generator includes an interferometer, and an optical feed-back loop waveguide.

Abstract: A full-parallax acousto-optic/electro-optic holographic video display includes a control layer and a piezo-electric layer, which includes a substrate and an array of anisotropic waveguide elements. Each waveguide element guides light into a single polarization and includes a horizontal grating, which diffracts light horizontally and comprises surface acoustic waves, and vertical grating, which diffracts light vertically and includes an electro-optic phased array. The surface acoustic waves propagate linearly with the guided, polarized light in the waveguide, converting the polarized light into a leaky mode of orthogonal polarized light. The combination of the horizontal and vertical gratings allows the waveguide element to focus light to multiple points and steer it in order to form a holographic image. The horizontal grating may be generated by interdigital acousto-optic transducers and the vertical grating may be controlled by electro-optic transducers.

Abstract: An optical modulator device comprising an interferometer. The interferometer includes an input optical coupler, an output optical coupler, and two or more controllable optical waveguides located on a substrate. Each controllable optical waveguide connects the input optical coupler to the output optical coupler and has two-state modulator along a segment thereof. The two or more controllable optical waveguides are connected to transmit an output to the output optical coupler, substantially different light amplitudes and/or phases when the two-state modulators of the two controllable optical waveguides are in different states, as driven by data streams having different information content. The two or more controllable optical waveguides are configured to modulate the light amplitudes and/or phases in a substantially same manner when the two-state modulators are in identical states.

Abstract: An optical IQ modulator (10) comprising•a modulator input port (11);•a modulator output port (12);•a plurality of optical branches (13) connected in parallel therebetween;•each optical branch (13) comprising an optical interferometer (1), each optical interferometer (1) comprising•an optical splitter (2);•an optical combiner (3); and,•a plurality of optical paths (4) connected therebetween:•at least one electrode (7) arranged in close proximity to an optical path (4) for altering the phase of an optical signal passing along the path (4);•the optical splitter (2) being in being in optical communication with the modulator input port (11) and being adapted to split light received from the modulator input port (11) into the plurality of optical paths (4);•the optical combiner (3) having an optical output port (5) in optical communication with the modulator output port (12), the optical combiner (3) being adapted to combine the optical signals from the plurality of optical paths (4) at the output port (5);•at leas

Abstract: The invention relates to waveguide optical modulators wherein two or more waveguides are modulated with specific modulation strengths using a single straight signal electrode or a single multi-segment signal electrode. Modulation strengths for each of a plurality of waveguides modulated by a single multi-segment electrode are matched over a wide modulation frequency range. Linearized output characteristics with respect to second and third order distortions arc achieved in one aspect of the invention.

Abstract: Methods and systems for a low-voltage integrated silicon high-speed modulator may include an optical modulator comprising first and second optical waveguides and two optical phase shifters, where each of the two optical phase shifters may comprise a p-n junction with a horizontal section and a vertical section and an optical signal is communicated to the first optical waveguide. A portion of the optical signal may then be coupled to the second optical waveguide. A phase of at least one optical signal in the waveguides may be modulated utilizing the optical phase shifters. A portion of the phase modulated optical signals may be coupled between the two waveguides, thereby generating two output signals from the modulator. A modulating signal may be applied to the phase shifters which may include a reverse bias.

Abstract: An electro-optic modulator includes a substrate comprising a surface, a pair of transmission lines formed in the surface and extending substantially in parallel with each other, a pair of first strip electrodes formed on the surface and covering the respective transmission lines, and a pair of second strip electrodes positioned at two sides of the first strip electrodes and parallel with the first strip electrodes.

Abstract: An optical modulator comprises a bulk-silicon substrate comprising a trench having a predetermined width and a predetermined depth. A bottom cladding layer is formed in the trench, and a plurality of waveguides and a phase modulation unit are formed on the bottom cladding layer. A top cladding layer is formed on the plurality of waveguides and the phase modulation unit.

Abstract: Embodiments of the present invention provide stable lithium niobate waveguide devices, and methods of making and using the same. A lithium niobate-based waveguide device may include a Z-cut lithium niobate substrate having upper and lower surfaces, an optical waveguide embedded within the lithium niobate substrate, a signal electrode disposed on the upper surface of lithium niobate substrate and parallel to the optical waveguide, guard electrodes disposed on the upper surface of the lithium niobate substrate and flanking but spaced apart from the signal electrode, and a conductive layer on the lower surface of the lithium niobate substrate, wherein the conductive layer serves as a common ground reference for the signal and guard electrodes.

Abstract: An optical sub assembly can include a distributed feedback (DFB) tunable laser and an optical modulator. Wavelength selection and phase adjustment portions of the DFB laser, as well as an electro-optic (EO) modulator can be formed from polymer waveguides including hyperpolarizable chromophores disposed on a single substrate.

Abstract: A Mach-Zehnder optical modulator includes a join-and-branch portion; two light wave guides connected with the join-and-branch portion; an output light waveguide connected with the join-and-branch portion; arm electrodes respectively provided on the two light waveguides; and a ground electrode that is provided at an edge of at least one of the arm electrodes along the light waveguide, is spaced from the arm electrode and is grounded.

Abstract: An optical modulator includes: laser diodes disposed in parallel with each other, each laser diode having a different lasing wavelength; optical waveguides disposed in parallel with each other with first ends facing the laser diodes; an optical isolator inserted between the laser diodes and the optical waveguides and attenuating return light reflected from the optical waveguides toward the laser diodes; a lens focusing light emitted from the laser diodes onto the optical waveguides through the optical isolator; an optical switch selecting one of the light beams exiting from the optical waveguides; and an optical modulator modulating the light beam selected by and output from the optical switch.

Abstract: A semiconductor optical modulator includes optical input and output portions; a plurality of Mach-Zehnder modulators including first and second waveguide arms having first and second modulation electrodes, respectively; an optical demultiplexer coupled between the optical input portion and the Mach-Zehnder modulator through an optical waveguide; an optical multiplexer coupled between the optical output portion and the Mach-Zehnder modulator; a plurality of electrical inputs including first, second, and common electrodes disposed between the first and second electrodes; and a plurality of differential transmission lines electrically connecting the electrical inputs to the Mach-Zehnder modulators. The Mach-Zehnder modulators, the optical demultiplexer, the optical multiplexer, the electrical inputs, and the differential transmission lines are disposed on a single substrate.

Abstract: A device, such as a silicon modulator, in accordance with the present disclosure employs PN diodes without sacrificing the modulation depth, while achieving lower loss and better impedance matching to 50-Ohm drivers. In one embodiment, the device includes an input waveguide, an input optical splitter coupled to the input waveguide, first and second optical phase shifters coupled to the input optical splitter, an output optical splitter coupled to the first and second phase shifters, and an output waveguide coupled to the output optical splitter. The phase shifters are designed with variant capacitance per unit length.

Abstract: An optical modulator uses an optoelectronic phase comparator configured to provide, in the form of an electrical signal, a measure of a phase difference between two optical waves. The phase comparator includes an optical directional coupler having two coupled channels respectively defining two optical inputs for receiving the two optical waves to be compared. Two photodiodes are configured to respectively receive the optical output powers of the two channels of the directional coupler. An electrical circuit is configured to supply, as a measure of the optical phase shift, an electrical signal proportional to the difference between the electrical signals produced by the two photodiodes.

Abstract: A Mach-Zehnder interferometer useful for analog or digital optical signal manipulation. In one example, the MZI is configured as an optical device that provides a balanced output. In another example, the MZI is configured as an optical device that provides a single ended output. Each device uses a silicon split or slotted wave guide having an electro-optically active material present within the slot. The balanced output device uses two slotted wave guides in push-pull configuration.

Abstract: An optical demultiplexer has first and second input ports and first and second output ports. When optical signal is introduced into the first input port, intensity of optical signal output from the first output port is equal to that from the second output port. When optical signal is introduced into the second input port, intensity of optical signal output from the first output port is larger than that from the second output port. An optical multiplexer has third and fourth input ports and third and fourth output ports. A first optical waveguide connects between the first output port and the third input port, while a second optical waveguide connects between the second output port and the fourth input port. Voltages applied to a first modulation electrode and a second modulation electrode work to cause changes in the optical path lengths of the first optical waveguide and the second optical waveguide.

Abstract: Provided is an optical element including an optical waveguide including a core formed from: a rib part; and a first and second slab parts sandwiching the rib part. The first slab part includes a P-type region, the second slab part includes an N-type region, the rib part includes a P-type region which is in contact with the P-type region provided in the first slab part, and an N-type region which is in contact with the N-type region provided in the second slab part. The rib part includes a top portion which is located above the first and second slab parts and includes an undoped region formed from at least one of an intrinsic region and a low-concentration doping region which is doped at a dopant concentration 1/10 or less of a dopant concentration in at least one of the adjacent P-type region and the adjacent N-type region.

Abstract: An optical waveguide device includes: a substrate which has an electro-optical effect; an optical waveguide which is formed on the substrate and/or inside the substrate; and an in-substrate electrode which is formed of a metal and provided inside the substrate.

Abstract: A method and structure for a modulator which includes a forward-biased diode optimized for power and area to perform a tuning function, and a reverse-biased diode optimized for speed to perform a modulation function.

Abstract: All-optical processing devices that include patterned optically active polymers. The devices that are constructed according to principles of the invention include at least one optical input port and at least one optical output port, respectively configured to accept optical input signals and provide optical output signals. The devices include optically active material such as organic polymers that interact with illumination at a first wavelength to change at least one optical property in a non-linear manner. The optically active polymer can be placed adjacent one or more waveguides that allow the input illumination to propagate. As the optical property of the optically active material is changed by the incident illumination, the propagating illumination undergoes a modulation or change in phase, thereby providing an optical output signal having a desired relation to the optical input signal, such as the result of a logical or a computational operation.

Abstract: A radiation modulator for a lithography apparatus, a lithography apparatus, a method of modulating radiation for use in lithography, and a device manufacturing method is disclosed. The radiation modulator for a lithography apparatus may have a plurality of waveguides supporting propagation therethough of radiation having a wavelength less than 450 nm; and a modulating section configured to individually modulate radiation propagating in each of the waveguides in order to provide a modulated plurality of output beams.

Abstract: Improved optical interferometric modulators have a small waveguide spacing so that the waveguide pair are close to the central electrode, to enhance electro-optic interaction. Asymmetric waveguides with differential indices are used to effectively de-couple the waveguide pair. Multiple sections of asymmetric waveguide pairs with alternating differential indices are used to achieve chirp-free operation. Another version of the device utilizes transmission-line electrode that weave closer to one of the waveguide pair alternately between sections. Another version of the device utilizes waveguide structure that one of the waveguide is closer to the central electrode in alternate section. To improve efficiency further, a DC bias is provided on the outer electrodes configured as an RF-ground but DC-float electrodes. Another improvement is to have a slot is cut underneath the waveguide region to effectively reduce to thickness of the substrate. These improvements lead to higher modulator efficiency.

Abstract: A method for optical chirp-free optical polarization modulation includes dividing a data modulated optical signal into a first optical path and a second optical path, using a Mach-Zehnder intensity modulator in the first optical path for imparting a ? phase difference between adjacent symbols of the data modulated optical signal in the first optical path, adjusting a delay and amplitude of symbols of the data modulated optical signal in the second path so that the symbols in the first path and the symbols in the second path are synchronized and have substantially equal power levels, and combining the first and second optical paths so that symbols from the first and second optical paths are in orthogonal polarizations.

Abstract: A polarization controller includes a first polarization controller, a demultiplexer, a second polarization controller, and a multiplexer. The first polarization controller controls the state of polarization of input light such that a part of the wavelength components of the input light is in a first state of polarization. The demultiplexer demultiplexes the light output from the first polarization controller into a plurality of wavelength components. The second polarization controller controls the plurality of wavelength components in a second state of polarization by using liquid crystal modulation devices. The multiplexer multiplexes the plurality of wavelength components output from the second polarization controller.

Abstract: Endless phase shifting apparatus, structures, and methods useful—for example—in MIMO optical demultiplexing.

Abstract: An electro-optic Mach-Zehnder modulator includes a first optical waveguide forming a first arm of the Mach-Zehnder modulator, and a second optical waveguide forming a second arm thereof. The first or second optical waveguide includes capacitive segments that are spaced apart from one another, each forming an electrical capacitor. A travelling wave electrode arrangement applies a voltage across the first or second optical waveguide. The travelling wave electrode arrangement includes waveguide electrodes arranged on the capacitive segments , an electrical line extending along a part of the first or second optical waveguide, the electrical line being arranged a distance from the waveguide electrodes, and connecting arrangements, each being assigned to one of the waveguide electrodes.

Abstract: A Mach-Zehnder optical modulator includes a join-and-branch portion, two light wave guides connected with the join-and-branch portion, two output light waveguides connected with the join-and-branch portion, arm electrodes respectively provided on the two light waveguides, light intensity detection electrodes respectively provided on the two output light waveguides, and a leakage suppression electrode provided between the arm electrodes and the light intensity detection electrodes.

Abstract: An apparatus comprising a modulation block comprising a plurality of modulators, wherein each of the plurality of modulators comprises an optical input port and an optical output port, and wherein all of the optical input ports and all of the optical output ports are positioned on one face of the modulation block. Another apparatus comprising a modulation block comprising one or more Mach-Zehnder modulators (MZMs), wherein each MZM is coupled to an optical input port, an optical output port, and at least one electrical trace, wherein all of the optical input ports and all of the optical output ports are positioned on a first side of the modulation block, and wherein all of the electrical traces are positioned on a second side of the modulation block, and a planar lightwave circuit (PLC) coupled to the modulation block via an optical interface.

Abstract: An electro-optic modulator includes a substrate, a pair of transmission lines, a first strip-shaped electrode, and a pair of second strip-shaped electrodes. The substrate includes a surface and a reversely-polarized portion. The transmission lines are formed in the surface and extend substantially in parallel with each other. One of the transmission lines is formed within the reversely-polarized portion and the other is out of the reversely-polarized portion. The first strip-shaped electrode is formed on the surface and covers the transmission lines. The second strip-shaped electrodes are positioned at two sides of the first strip-shaped electrodes and parallel with the first strip-shaped electrode.

Abstract: Various exemplary embodiments relate to an optical isolator in an integrated optical circuit including: a first optical modulator configured to provide a first periodic phase modulation on an input optical signal; a second optical modulator configured to provide a second periodic phase modulation on the modulated optical signal; and an optical waveguide having a length L connecting the first optical modulator to the second optical modulator; wherein the phase difference between the first and second periodic phase modulation is ?/2, and wherein the length L of the optical waveguide causes a phase delay of ?/2 on an optical signal traversing the optical waveguide.

Abstract: An optical device comprising a tunable optical frequency comb generator. The comb generator includes an interferometer, and an optical feed-back loop waveguide.

Abstract: An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode for applying an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a modulation signal generator to generate the modulation signal of a first frequency; a superimposer to superimpose a signal of a second frequency different from the first frequency on the bias voltage; and a bias controller to control the bias voltage in a modulation direction of the modulator and the bias voltage in an orthogonal direction which is orthogonal to the modulation direction based on a phase of the second frequency component extracted from a modulated optical signal generated by the modulator.