Abstract: The invention relates to an optical modulator, comprising a first waveguide for a signal to be modulated, a second waveguide for a control signal, and an auxiliary waveguide, wherein the auxiliary waveguide is supported by a carrier which can be deflected to change a distance between the first waveguide and the auxiliary waveguide, wherein the carrier also comprises two layers with different coefficients of thermal expansion and the second waveguide is guided in such a way that a temperature of the carrier at least in a section can be manipulated by light transported by the second waveguide. The invention further relates to an integrated optical circuit comprising such an optical modulator, and to a modulation method which can be performed with such a modulator.

Abstract: An optical waveguide formed in a substrate including: a curved waveguide; and a splitter that is coupled to the curved waveguide and branches, wherein a low refraction index portion having an effective refraction index that is lower than that of a start point of the curved waveguide on an opposite side of the splitter is provided in a waveguide extending from the start point of the curved waveguide to the splitter.

Abstract: A method of amplitude electro-optic modulation. The method includes transmitting a narrowband laser light into an electro-optically active waveguide in a first direction. The electro-optically active waveguide has a grating for reflecting the narrowband laser light. The method also includes applying an electric signal to the electro-optically active waveguide and modifying the reflection of the grating in a wavelength region of the narrowband laser light by application of the electric signal.

Abstract: Embodiments of an optical device, an array of optical devices, and a technique for fabricating the optical device or the array are described. This optical device is implemented using two semiconductor layers (such as silicon), one of which includes a heater and the other includes a thermally tunable optical waveguide. Spatially separating these two functions in the optical device results in more efficient heat transfer between the heater and the optical waveguide, reduced heat transfer to the surroundings, and reduced optical losses in the optical waveguide relative to existing silicon-based optical devices.

Abstract: An optical modulator is provided which suppresses a radiation mode of a microwave generated in a connection substrate or a termination substrate from entering a signal electrode of the optical modulator and suppresses modulation properties from being degraded. The optical modulator includes an optical modulation element (1) having a substrate with an electro-optic effect, an optical waveguide formed on the substrate, and a modulating electrode (or a signal electrode (2)) for modulating light passing through the optical waveguide; and a connection substrate (4), arranged outside the substrate, for supplying the optical modulation element with a microwave signal operating the optical modulation element. A signal input terminal (22) and a signal output terminal (23) are formed on the connection substrate (20).

Abstract: A micro-ring configured to selectively detect or modulate optical energy includes at least one annular optical cavity; at least two electrodes disposed about the optical cavity configured to generate an electrical field in the at least one optical cavity; and an optically active layer optically coupled to the at least one optical cavity. A method of manipulating optical energy within a waveguide includes optically coupling at least one annular optical cavity with the waveguide; and selectively controlling an electrical field in the at least one annular optical cavity to modulate optical energy from the waveguide.

Abstract: An optical waveguide device module is provided, wherein a control electrode includes a signal electrode and ground electrodes disposed to sandwich the signal electrode, a connection substrate is provided with a signal line and ground lines disposed to sandwich the signal line, the distance W1 between the ground electrodes in the input end or the output end of the control electrode is larger than the distance W2 between the ground lines on the optical waveguide device side of the connection substrate, the control electrode has a portion of which the distance between the ground electrodes is smaller than the distance W2 in a portion away from the input end or the output end thereof, and interconnections of which the distance W between ground interconnections connecting the optical waveguide device and the connection substrate is at least smaller than the distance W1.

Abstract: The present invention relates to a device and a method for selective transmission of an optical signal. It is an object of the present invention to provide a light modulator and a method for light modulation capable of selecting very short optical pulses of up to the femtosecond range with a low repetition frequency, wherein the repetition frequency can be variable in a range between several Hz up to the GHz range. To this end, the device has a first optical waveguide (3), a first drive circuit (14), a second optical waveguide (1, 2) and a second drive circuit (15), wherein the spacing between a switching element of the first drive circuit (14) and the first optical waveguide (3) is less than 3 mm, and the distance between a switching element of the second drive circuit (15) and the second optical waveguide (1, 2) is less than 3 mm, and the first optical waveguide (3) has a first absorber section (5), a pulse picker section (4) and a second absorber section (18).

Abstract: An optical waveguide is formed on a ferroelectric substrate having a thickness of 20 ?m or less by diffusion of a dopant or ion exchange. The optical waveguide has a non-branched section 2a operating on single mode and a pair of branched sections branched from the non-branched section 2a. Each of the branched sections has a connecting part 7 extending from a branching end 10 and a multi mode propagating part 8 continuously formed from the connecting part 7. The multi mode propagating part 8 has a width “m” larger than a width “t” of the non-branched section. A width “p” of the connecting part increases from the non-branched section 2a toward the multi mode propagating part 8.

Abstract: The invention relates to an optical component including an array of coupled waveguides, wherein said waveguide array includes: a first area made of parallel waveguides coupled according to a first coupling coefficient; a second area adjacent to the first area and made of parallel waveguides coupled according to a second coupling coefficient lower than the first coupling coefficient; a third area adjacent to the second area and made of parallel waveguides coupled according to a third coupling coefficient higher than the second coupling coefficient; a fourth area adjacent to the third area and made of parallel waveguides coupled according to a fourth coupling coefficient lower than the third coupling coefficient; and a fifth area adjacent to the fourth area and made of parallel waveguides coupled according to a fifth coupling coefficient higher than the fourth coupling coefficient.

Abstract: An apparatus comprising an electronic-photonic device. The device includes a planar substrate having a top layer on a middle layer, active electronic components and active photonic waveguide components. The active electronic components are located on first lateral regions of the top layer, and the active photonic waveguide components are located on second lateral regions of the top layer. The second-region thickness is greater than the first-region thickness. The top layer has a higher refractive index than the middle layer.

Abstract: Optical interconnect systems and methods are disclosed. An optical interconnect system includes a substrate, an optical waveguide, and first and second modulators. The optical waveguide has a first waveguide portion extending to a first coupling structure, a second waveguide portion extending from the first coupling structure to a second coupling structure, and a third waveguide portion extending from the second coupling structure. The first modulator is positioned adjacent the first coupling structure, and the second modulator is positioned adjacent the second coupling structure. The optical interconnect method includes modulating light with a first modulator to produce one-time modulated light, and modulating the one-time modulated light with a second modulator to produce two-time modulated light.

Abstract: An optical modulator suppresses a radiation mode of a microwave generated in a connection substrate or termination substrate from entering a signal electrode of the optical modulator and suppresses modulation properties from being degraded. The optical modulator includes an optical modulation element (1) having a substrate with an electro-optic effect, an optical waveguide formed on the substrate, and a modulating electrode (or a signal electrode (2)) for modulating light passing through the optical waveguide; and a connection substrate (4), arranged outside the substrate, for supplying the optical modulation element with a microwave signal operating the optical modulation element. A signal input terminal (22) and a signal output terminal (23) are formed on the connection substrate (20).

Abstract: The present invention can provide an npin-type optical modulator that has a high withstand voltage and is easily fabricated. A semiconductor optical amplifier (10) according to an embodiment of the present invention is an npin-type semiconductor optical modulator in which layers are sequentially stacked, with a cathode layer (12-1) arranged on the substrate side, including at least a first n-type cladding layer (13-1), a p-type cladding layer (14), a core layer (17) and a second n-type cladding layer (13-2). In this semiconductor optical modulator, the p-type cladding layer (14) is electrically connected to an electrode (18-1) of the cathode layer. Accordingly, the accumulation of holes in the p-type cladding layer associated with light absorption in the npin-type optical modulator can be absorbed in the electrode on the negative side.

Abstract: The present invention is directed to provide a light modulation device capable of not only restricting the faint light propagating in the adhesive layer from being re-incident on the thin substrate but also increasing an adhesive strength of the thin substrate and the supplementing plate. The invention is characterized in a light modulation device having a thin substrate 1 made of material with an electro-optical effect and with a thickness of below 20 ?m; an optical waveguide 2 formed on a surface of the thin substrate or the other surface thereof; and a modulation electrode 3 formed on the surface of the thin substrate and for modulating light passing through the optical waveguide, comprising: a supplementing plate 5 adapted to be bonded to the thin substrate via an adhesive layer 4, wherein a bonding surface of the supplementing plate is formed as a rough surface 10 relative to a bonding surface of the thin substrate.

Abstract: The optical device includes a substrate having an electrooptic effect; a plurality of optical waveguides formed in the substrate in parallel to one another; and a polarization inversion region which is disposed a part of the substrate and which has a polarization characteristic that is an inverse to that of the substrate, wherein a profile of a boundary between the polarization inversion region and a remaining region in which the polarization is not inverted is configured such that accumulated amounts of distortion that affects the respective waveguides over coordinates along a light propagation direction are substantially identical.

Abstract: An all-optical XOR logic gate. In one embodiment, a single photon absorption medium is used to provide enhanced optical response of a gate to an applied optical signal. The apparatus described uses at least two gate inputs and an optical modulation structure such as a Mach-Zehnder interferometer to perform logical XOR operations on an optical input signal using the gate inputs. The result of the XOR operation is provided as information in an optical output signal representative of the result of the XOR operation impressed on the optical input signal.

Abstract: An optical modulator includes a modulation region for modulating light, and a passive region adjacent the modulation region. The modulation region and the passive region include, in common, a semiconductor substrate, an n-type cladding layer on the semiconductor substrate, a core layer on the n-type cladding layer, and a p-type cladding layer on the core layer. The modulation region further includes a contact layer on the p-type cladding layer, and a P-side electrode on the contact layer. The passive region further includes an undoped cladding layer between the core layer and the p-type cladding layer.

Abstract: The thermo-optic phase shifter (200) according to an exemplary aspect of the invention includes: a substrate (201); a sacrificial layer (202) formed above the substrate (201); a first cladding layer (203) formed above the sacrificial layer (202) and having a film density higher than that of the sacrificial layer (202); an optical waveguide core (204) formed above the first cladding layer (203); a second cladding layer (205) provided over the first cladding layer (203) to cover the optical waveguide core (204); a heat-generating heater (206) provided to a region of the second cladding layer (205) directly above the optical waveguide core (204); and a groove (207) formed in a side face region of the optical waveguide core (204) and extending from the surface of the second cladding layer (205) to the surface of the substrate (201).

Abstract: A vector-matrix multiplier is disclosed which uses N different wavelengths of light that are modulated with amplitudes representing elements of an N×1 vector and combined to form an input wavelength-division multiplexed (WDM) light stream. The input WDM light stream is split into N streamlets from which each wavelength of the light is individually coupled out and modulated for a second time using an input signal representing elements of an M×N matrix, and is then coupled into an output waveguide for each streamlet to form an output WDM light stream which is detected to generate a product of the vector and matrix. The vector-matrix multiplier can be formed as an integrated optical circuit using either waveguide amplitude modulators or ring resonator amplitude modulators.

Abstract: A transmitter apparatus (2) is described that comprises one or more lasers (4), modulation means (10) to intensity modulate radiation output by each of said one or more lasers (4), and output means for outputting the modulated radiation produced by the modulation means into, for example, an optical fiber (22). The apparatus comprises hollow core optical waveguides (20) formed in a substrate (18) which, in use, guide radiation from the one or more lasers (4) to the modulation means (10) and from the modulation means (10) to the output means. An associated receiver apparatus (30) is also described that comprises one or more detectors (32) and one or more optical fiber attachment means, the one or more optical fiber attachment means being arranged to receive one or more one optical fibers (42). The receiver is characterized in that radiation is guided from the one or more optical fibers (42) to the one or more detectors (32) by at least one hollow core optical waveguide (40) formed in a substrate.

Abstract: A Mach-Zehnder type optical modulator includes an optical waveguide formed in an electro-optical substrate, an input section that inputs light to the optical waveguide, a plurality of branch modulation sections that generate branched input light, extend from the input section and modulate the branched input light, an interference photocoupler including a plurality of input ports and a plurality of output ports, the input ports being coupled to the branch modulation sections, and an output photocoupler including a plurality of input ports coupled to the output ports of the interference photocoupler and also including a plurality of output ports.

Abstract: This invention provides a versatile unit cell as well as programmable and reconfigurable optical signal processors (such as optical-domain RF filters) that are constructed from arrays of those unit cells interconnected by optical waveguides. Each unit cell comprises an optical microdisk, an optical phase shifter, and at least one input/output optical waveguide, wherein the microdisk and the phase shifter are both optically connected to a common waveguide.

Abstract: An optical NOR gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical NOR gate utilizes two digital optical inputs and a continuous light input to provide a NOR function digital optical output. The optical NOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 ?m.

Abstract: A phase modulation waveguide structure includes one of a semiconductor and a semiconductor-on-insulator substrate, a doped semiconductor layer formed over the one of a semiconductor and a semiconductor-on-insulator substrate, the doped semiconductor portion including a waveguide rib protruding from a surface thereof not in contact with the one of a semiconductor and a semiconductor-on-insulator substrate, and an electrical contact on top of the waveguide rib. The electrical contact is formed of a material with an optical refractive index close to that of a surrounding oxide layer that surrounds the waveguide rib and the electrical contact and lower than the optical refractive index of the doped semiconductor layer. During propagation of an optical mode within the waveguide structure, the electrical contact isolates the optical mode between the doped semiconductor layer and a metal electrode contact on top of the electrical contact.

Abstract: In an electro-optic device, a stack structure including a first silicon layer of a first conductivity type and a second silicon layer of a second conductivity type has a rib waveguide shape so as to form an optical confinement area, and a slab portion of a rib waveguide includes an area to which a metal electrode is connected. The slab portion in the area to which the metal electrode is connected is thicker than a surrounding slab portion. The area to which the metal electrode is connected is set so that a range of a distance from the rib waveguide to the area to which the metal electrode is connected is such that when the distance is changed, an effective refractive index of the rib waveguide in a zeroth-order mode does not change.

Abstract: An optical resonator configured to be tuned using a charge-based memory cell includes an optical cavity configured to transmit light and receive injected charge carriers; a charge-based memory cell in proximity to or within the optical cavity, the memory cell containing a number of trapped charges which influence the resonant optical frequency of the optical resonator. A method of tuning an optical resonator includes applying a voltage or current to a charge-based memory cell to generate a non-volatile charge within the memory cell, the nonvolatile charge changing a resonant frequency of the optical resonator.

Abstract: Embodiments of the present invention provide for enhanced monitoring of optical signal characteristics of an optical signal propagating in a signal channel of a photonic integrated circuit. The optical signal characteristics can be obtained with minimal signal loss in the optical signal path and reduced RF crosstalk, while the electrostatic discharge threshold for the photonic integrated circuit is increased, due to the inclusion of a second electro-optic element electrically coupled to a first electro-optic element as part of the signal channel.

Abstract: An optical waveguide of the present invention is an optical waveguide in order to directly introduce light beams emitted from a light emitting element. In a core that is a waveguide through which light propagates, a concave part is formed that is a depression in a light incident end surface that is one side where light enters. Therefore, an optical waveguide is realized that can obtain a large optical coupling efficiency is possible by the operation of phase alignment in the concave part.

Abstract: An optical device includes a light-transmitting medium positioned on a base. The light-transmitting medium includes a slab region and a ridge extending upward from the slab region. The ridge defines a portion of an optical waveguide on the device. A modulator is also positioned on the base. The modulator includes a first doped region of the light-transmitting medium and a second doped region of the light-transmitting medium. The first doped region and the second doped region are configured such that a depletion region forms in the waveguide when an electrical bias is not applied to the modulator. At least a portion of the first doped region is positioned in the ridge and at least a portion of the second doped region is positioned in the slab region. The light-transmitting medium includes a first electrical pathway extending from a first location to the first doped region. The first location is on top of the light-transmitting medium and is spaced apart from the ridge.

Abstract: It is provided a polarization-independent optical isolator without depending on the polarized wave of the light being input to the waveguide-type optical isolator, in particular, it is able to completely isolate the propagating light of the backward direction.

Abstract: An optical modulator component 2 has a substrate 4 for modulation made of an electro-optical material and having a joining face 4b; an optical waveguide 6 provided in or on the substrate 4 and having at least one pair of branched portions 6c; and a radio-frequency interaction portion 11 applying a voltage on the respective branched portions 6c to modulate light propagating through the branched portions. The optical waveguide 6 has end faces 15A, 15B, 15C and 15D present on the joining face 4b of the substrate 4 for modulation.

Abstract: Titania is a semiconductor and photocatalyst that is also chemically inert. With its bandgap of 3.0, to activate the photocatalytic property of titania requires light of about 390 nm wavelength, which is in the ultra-violet, where sunlight is very low in intensity. A method and devices are disclosed wherein stress is induced and managed in a thin film of titania in order to shift and lower the bandgap energy into the longer wavelengths that are more abundant in sunlight. Applications of this stress-induced bandgap-shifted titania photocatalytic surface include photoelectrolysis for production of hydrogen gas from water, photovoltaics for production of electricity, and photocatalysis for detoxification and disinfection.

Abstract: An optically powered optical modulator comprises an optical modulation component, such as an electro-optical modulator, acousto-optic modulator or magneto-optic modulator, in combination with one or two lens assemblies positioned at one or both apertures of the optical modulation component, so that the optical modulator formed by the combination of the lens assembly or assemblies and the optical modulation component has optical focus power.

Abstract: Disclosed herein is an optical frequency shifter (1) provided with: an electro-optical substrate (3) having a main surface (3a); an optical waveguide structure (2) formed in the substrate (3) and having two waveguide portions (7), which are spaced apart by a distance (S) such as to ensure mutual optical coupling therebetween; and an electrode structure (10) arranged above the main surface (3a) of the substrate (3) and having at least a first electrode (11). The substrate (3) has a Z-cut crystalline structure with Z crystal axis orthogonal to the main surface (3a) and comprises two oppositely poled portions (20, 21) having opposite orientations of the Z crystal axis; the two waveguide portions (7) are arranged underneath the first electrode (11), each in a respective one of the two oppositely poled portions (20, 21).

Abstract: An optical modulator is formed with at least a portion of a semiconductor layer (8) that has undergone a doping process to exhibit a first conductivity and at least a portion of a semiconductor layer (9) that has undergone a doping process to exhibit a second conductivity overlapping with a dielectric layer (11) interposed. The surface of the semiconductor layer (8) of first conductivity has an uneven form in the portion in which the semiconductor layer (8) that exhibits first conductivity and the semiconductor layer (9) that exhibits second conductivity overlap with the dielectric layer (11) interposed. The dielectric layer (11) is formed on the semiconductor layer (8) of first conductivity that has the uneven form, and the semiconductor layer (9) of second conductivity is formed on the dielectric layer (11).

Abstract: A frequency up-conversion system includes an optical splitter, an optical modulator, an optical phase-shifter, and an optical coupler. In one embodiment of the present disclosure, the optical splitter is configured to split an optical wave into a first optical wave and a second optical wave, the optical modulator is configured to modulate the first optical wave to form a modulation wave, the optical phase-shifter is configured to shift the phase of the second optical wave by a predetermined phase to form a shifting wave, and the optical coupler is configured to couple the modulation wave and the shifting wave. In one embodiment of the present disclosure, the optical modulator and the optical phase-shifter are connected in a parallel manner.

Abstract: An integrated circuit that includes an optical waveguide to convey an optical signal via an optical mode in an on-chip optical waveguide is described. In this integrated circuit, a cross-sectional area of the optical waveguide may be tapered in proximity to an electro-optic modulator in the integrated circuit, such as a germanium electro-optic modulator or a quantum-well (QW) electro-optic modulator. In particular, the cross-sectional area may be tapered from a first diameter distal from the electro-optic modulator to a second diameter proximate to the electro-optic modulator. This so-called ‘inverse taper’ may increase the spatial extent or size of the optical mode, thereby allowing the optical signal to be optically coupled to or from the electro-optic modulator with low optical loss.

Abstract: Electro-optic modulators are disclosed. An electro-optic modulator comprises an electro-optic polymer layer, semiconductor layers, ferroelectric material layers, and electrodes. The semiconductor layers are positioned on each surface of the electro-optic polymer layer. The refractive index of the semiconductor layers in the optical and RF domains is higher than the refractive index of the electro-optic polymer layer in the optical and RF domains. The ferroelectric material layers are positioned on each semiconductor layer opposite the electro-optic polymer layer. The refractive index of the ferroelectric material layers in the RF domain is higher than the refractive indices of both the electro-optic polymer layer and the semiconductor layers in the RF domain. The refractive index of the ferroelectric material layers in the optical domain is lower than the refractive index of the semiconductor layer in the optical domain.

Abstract: A method is provided for visual inspection of an array of interferometric modulators in various driven states. This method may include driving multiple columns or rows of interferometric modulators via a single test pad or test lead, such as test pad, and then observing the array for discrepancies between the expected optical output and the actual optical output of the array. This method may particularly include, for example, driving a set of non-adjacent rows or columns to a state different from the intervening rows or columns and then observing the optical output of the array.

Abstract: A single-photon absorption all-optical signal-processing device, systems employing the same, and methods of making and using the same. Illustrative examples are provided based on silicon semiconductor technology that employs rectangular waveguides fabricated on SOI wafers. In some embodiments, it is observed that the waveguides have surface state density, ?, of not less than 1.5×1018 cm?1s?1mW?1 to provide a single-photon absorption operation mode. In some embodiments, some portion of the ridge waveguide structure has a surface to volume ratio of at least 18 ?m?1, computed using a unit length of 1 ?m of the waveguide, with the width and depth dimensions of the waveguide being measured in units of microns.

Abstract: It's an object of the invention to provide an optical modulator with high performance. The optical modulator 1 includes a substrate 4 having an electro-optical effect, an optical waveguide 5 formed on the substrate, and control electrodes 61 to 65 for controlling optical waves propagating in the optical waveguide, wherein the optical waveguide 5 includes a main Mach-Zehnder (MZ) type waveguide 50 having two branch waveguides and sub Mach-Zehnder (MZ) type waveguides 51 and 52 disposed in the branch waveguides, respectively, an optical intensity adjusting means (for example, including optical waveguides 53 and 54 and control electrodes 63 and 64) is disposed in each branch waveguide in series with the sub Mach-Zehnder type waveguides 51 and 52, and the optical modulator further comprises a voltage control circuit that monitors some of the optical waves propagating in the branch waveguides and adjusts a voltage applied to the optical intensity adjusting means.

Abstract: A communication system capable of employing polarization-dependent phase modulators with a reversing configuration that preserves security against disturbance of a polarization state at a transmission path but without using Faraday mirrors and a communication method using the same are provided. A quantum cryptography system of the present invention includes a first station 1, a transmission path 2, and a second station 3. The first station 1 has means for emitting time-divided optical pulses into the transmission path 2 and measuring a phase difference between the optical pulses returning from the transmission path 2. The transmission path 2 is a medium of light.

Abstract: An optical modulator 24 has a supporting substrate 5, a modulating substrate 11 made of an electro-optical material, an optical waveguide 12 provided on the side of a first main surface 30 of the modulating substrate 11, and an adhesion layer 6 adhering a second main surface 31 of the modulating substrate 11 onto the supporting substrate 5. The modulating substrate 11 has a high-frequency interaction portion 11c applying a voltage on the optical waveguide 12 to modulate propagating light, an incident portion 11a inputting light to the optical waveguide, and an outgoing portion 11b outputting light from the optical waveguide. The high-frequency interaction portion 11c is recessed on the first main surface 30 of the modulating substrate 11 with respect to the incident and outgoing portions 11a and 11b. The high-frequency interaction portion 11c has a thickness smaller than the those of the incident and outgoing portions 11a and 11b.

Abstract: An optical hybrid circuit includes a multimode interference coupler; a first 2:2 optical coupler; a second 2:2 optical coupler; a third 2:2 optical coupler; and a phase controlling region. The first 2:2 optical coupler, the second 2:2 optical coupler, and the third 2:2 optical coupler are coupled to one of the pair of first output channels, the pair of second output channels, the pair of third output channels, and the pair of fourth output channels of the multimode interference coupler. The phase controlling region is provided in one or both of each pair of at least two pairs of output channels from among three pairs of output channels to which the first 2:2 optical coupler, the second 2:2 optical coupler, and the third 2:2 optical coupler are coupled, respectively.

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: 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: A modulator includes an electro-optical substrate and a first and second waveguide formed of a doped semiconductor material positioned on a surface of an electro-optical substrate forming a slot therebetween. A doping level of the semiconductor material being chosen to make the first and second waveguide conductive. A dielectric material is positioned in the slot which increases confinement of both an optical field and an electrical field inside the slot. A refractive index of the semiconductor material and a refractive index of the dielectric material positioned in the slot being chosen to reduce the V?·L product of the modulator.

Abstract: The optical device includes a waveguide on a base. The device also includes a modulator on the base. The modulator includes an electro-absorption medium configured to receive a light signal from the waveguide. The modulator also includes field sources for generating an electrical field in the electro-absorption medium. The electro-absorption medium is a medium in which the Franz-Keldysh effect occurs in response to the formation of the electrical field in the electro-absorption medium. The field sources are configured so the electrical field is substantially parallel to the base.

Abstract: The ring resonator includes waveguides configured to guide light signals. The waveguides include an input waveguide and one or more loop waveguides. One of the loop waveguides is a primary loop waveguide that is optically coupled with the input waveguide at a wavelength of light. A tuner is configured to tune the wavelength at which the light is optically coupled from the input waveguide into the primary loop waveguide. One or more light detectors are each configured to provide an output indicating an intensity of light guided in one of the one or more loop waveguides. Electronics are configured to tune the tuner in response to the output from the light detector.