Abstract: Provided are a semiconductor optical modulator and a semiconductor Mach-Zehnder optical modulator of high efficiency and high reliability.

Abstract: Provided is a small optical waveguide device with little reflected light, the optical waveguide device including: an optical waveguide element of which a first output waveguide is inclined with respect to an output end face and a second output waveguide is inclined with respect to both the first output waveguide and the output end face; and a lens that allows beams respectively output from the first and second output waveguides to be parallel to each other.

Abstract: The invention relates to a device, system, and method for optimizing and altering electromagnetic frequency using Doppler shifts of electromagnetic radiation, and, in particular, optimizing frequency for application to photovoltaic devices and the like. The device comprises a crystal positioned in a channel undergoing a vibration, wherein an interaction between an incoming electromagnetic radiation and the vibration of the crystal optimizes a frequency of electromagnetic radiation.

Abstract: The present invention provides an electro-optic device comprising three or more radio-frequency (RF) signal electrodes, which each include an input segment. The input segments of the three or more RF-signal electrodes are arranged in a fractal pattern followed in an RF-signal transit direction by a parallel-bend pattern. Advantageously, this arrangement allows matching of RF-signal transit times of the input segments and near matching of RF-signal losses of the input segments.

Abstract: An optical splitter, a combiner and a device. The optical splitter comprises a first longitudinal waveguide for receiving an incoming light wave; at least first and second pairs of output waveguides, the output waveguides of each pair being disposed on opposite sides of the first waveguide; wherein each of the output waveguides of each pair comprises a longitudinal portion disposed parallel to the first waveguide and such that optical power is coupled from the first waveguide into the respective longitudinal portions and the longitudinal portions of output waveguides of the first and second pairs are displaced along a length of the first waveguide; wherein each of the output waveguides of each pair further comprises a substantially S-shaped portion continuing from the respective longitudinal portions and such that optical power coupling between the respective S-shaped portions of output waveguides of the first and second pairs is substantially inhibited.

Abstract: An integrated circuit is configured for optical communication via an optical polymer stack located on top of the integrated circuit. The optical polymer stack may include one or more electro-optic polymer devices including an electro-optic polymer. The electro-optic polymer may include a host polymer and a second order nonlinear chromomophore, the host polymer and the chromophore both including aryl groups configured to interact with one another to provide enhanced thermal and/or temporal stability.

Abstract: An optical polarization rotator includes first and second optical waveguide ribs located along a planar surface of a substrate. The second optical waveguide rib is located farther from the surface than the first optical waveguide rib. First segments of the optical waveguide ribs form a vertical stack over the substrate, and second segments of the optical waveguide ribs are offset laterally in a direction along the planar surface. The first and second optical waveguide ribs are formed of materials with different bulk refractive indexes.

Abstract: Herein disclosed is an optical modulator, having: a substrate (1); and a center and ground electrodes (4a to 4c), in which the substrate has ridge portions (8a to 8c), the center and ground electrodes are respectively formed above the ridge portions, the ridge portions below the center and ground electrodes respectively have top parts (10a, 10b) having a respective first and second end points (18, 19) separated with a distance of “WR”, the substrate has a bottom surface (21b) between the ridge portions having center and midway points (23, 24) positioned with a respective distance of WR/2 and WR/N (3?N?25) from the first end point, the ridge portion below the center electrode has a normal line (13), and the center point and the midway point define a straight line (25) crossed with the normal line at an angle larger or equal to 90.1°.

Abstract: In a conventional optical signal processing device, a confocal optical system is configured in which a focusing lens is positioned at a substantially-intermediate point of a free space optical path. Thus, the free space optical system had a long length. It has been difficult to reduce the size of the entire device. The optical signal processing device of the present invention uses a lens layout configuration different from the confocal optical system to thereby significantly reduce the length of the system. The optical signal processing device consists of the first focusing lens positioned in the close vicinity of a signal processing device, and the second focusing lens positioned in the vicinity of a dispersing element. A distance between the dispersing element and the signal processing device is approximately a focal length of the first focusing lens. Compared with the conventional technique, the length of the optical path can be halved.

Abstract: An electro-optic waveguide polarisation modulator includes cladding layers, and a waveguide core sandwiched between the cladding layers, wherein the waveguide core has a higher refractive index than the cladding layers. The modulator further includes primary electrodes arranged on the opposite side of one cladding layer to the core and a secondary electrode arranged on the opposite side of another cladding layer to the core. The electrodes are arranged to provide an electric field having field components in perpendicular directions within the waveguide core so as to modulate the refractive index such that electromagnetic radiation propagating through the core is converted from a first polarisation state to a second polarisation state. The modulator further includes a grading layer sandwiched between the cladding layers and the core, the grading layer having an effective refractive index intermediate between that of the waveguide core and the cladding layer.

Abstract: A process to manufacture a semiconductor optical modulator is disclosed, in which the process easily forms a metal film including AuZn for the p-ohmic metal even a contact hole has an enhanced aspect ration. The process forms a mesa including semiconductor layers first, then, buries the mesa by a resin layer sandwiched by insulating films. The resin layer provides an opening reaching the top of the mesa, into which the p-ohmic metal is formed. Another metal film including Ti is formed on the upper insulating film along the opening.

Abstract: A passive optical waveguide is solely built on a Si substrate while still maintaining high optical quality. Two side-by-side diamond shaped cavities may be etched into the Si wafer and oxide grown on the inner walls of the cavities until the oxide meets at opposing inner vertices of the diamond shaped cavities. An optical waveguide is formed by the inverted, generally triangular cross-sectional, portion of silicon remaining between the top surface of the wafer and the opposing inner vertices.

Abstract: The present invention discloses an ultra-compact optical modulator comprising at least one resonator on a semiconductor chip. The EO modulator modulates incoming light having a certain wavelength range and comprises a waveguide layer accommodating at least one resonator having a periodic complex refraction index distribution structure defining a periodic defect band-edge and a cladding layer; and at least one electrode; the waveguide layer, the cladding layer and the electrode forming a capacitor structure; such that when an external voltage is applied to the capacitor structure the free carrier concentration in the waveguide layer is controlled, enabling a modulation of the resonator's refractive index; wherein the periodic defect band-edge is selected to be within the wavelength range, enabling a slow-light propagation of the incoming light within the waveguide layer.

Abstract: The present invention provides an organic fibrous photovoltaic device with a frequency conversion region comprising a waveguide being arranged normal to the axis of the fiber.

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 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.

Abstract: An absorption modulator is provided. The absorption modulator includes a substrate, an insulation layer disposed on the substrate, and a waveguide having a P-I-N diode structure on the insulation layer. Absorptance of an intrinsic region in the P-I-N diode structure is varied when modulating light inputted to the waveguide. The absorption modulator obtains the improved characteristics, such as high speed, low power consumption, and small size, because it greatly reduces the cross-sectional area of the P-I-N diode structure.

Abstract: An RF photonic link having at least one light source, at least one photodetector, multiple optoelectronic modulators, and an RF waveguide common to each one of said multiple optoelectronic modulators. The multiple optoelectronic modulators are optically arranged in parallel to receive light from said at least one light source and are disposed in said RF waveguide. The RF waveguide, in use, guides an RF electromagnetic field applied to each of the multiple optoelectronic modulators disposed therein, the RF electromagnetic field propagating through the RF waveguide in a direction that is perpendicular to a direction in which an optical field propagates through each of said optoelectronic modulators.

Abstract: Examples of apparatus and methods are provided for controlling a bias in an optical modulator. An exemplary apparatus may comprise an optical modulator operable to modulate an optical signal. The optical modulation apparatus may comprise a photodetector disposed to receive at least a portion of the modulated optical signal. The optical modulation apparatus may comprise a bias controller coupled to both the optical modulator and the photodetector. The bias controller may be configured to receive a dither signal and to produce a bias feedback signal for the optical modulator. The bias feedback signal may be based on a ratio between an odd order harmonic signal of the modulated optical signal and an even order harmonic signal of the modulated optical signal.

Abstract: In an optical modulator comprising substrate 1 having electro-optical effect, two optical waveguides 3a, 3b formed in the substrate, buffer layer 2 formed on the substrate, traveling-wave electrode 4 having center conductor 4a and ground conductors 4b, 4c above the buffer layer, and ridge sections formed with recessed sections 9a to 9c by carving at least a part of the substrate where an electrical field strength of high-frequency electrical signal propagating the traveling-wave electrode is strong, in which the ridge sections include center conductor ridge section 8a having the center conductor formed above and ground conductor ridge section 8b having the ground conductor formed above, and the center conductor ridge section has one of the two optical waveguides formed therein, the recessed sections are practically symmetrical to the center line between the two optical waveguides and the traveling-wave electrode is practically symmetrical to the center line of the center conductor.

Abstract: An electro-optic device is disclosed, in which an RF signal electrode is used as a bias ground electrode. Thus, for Z-cut lithium niobate electro-optic crystals, there is no need to place a buried bias electrode under the RF signal electrode and over the optical waveguide. As a result, both optical and the RF wave propagation losses are reduced. In another embodiment, a buried bias electrode is placed over the optical waveguide between two buffer layers having a different electrical conductivity. The buffer layer underneath the buried bias electrode has a larger electrical conductivity than the buffer layer above the buried bias electrode. The buffer layer underneath the buried bias electrode reduces the optical loss penalty due to the buried bias electrode located above the optical waveguide, while the buffer layer above the bias electrode reduces leakage currents.

Abstract: An optoelectronic device includes an input waveguide structure that receives an input optical signal. A GeSi/Si waveguide structure receives from the input waveguide the input optical signal and performs selective optoelectronic operations on the input optical signal. The GeSi/Si waveguide structure outputs an optical or electrical output signal associated with the selective optoelectronic operations performed on the input optical signal. An output waveguide structure receives the output optical signal from the GeSi/Si waveguide structure and provides the optical output signal for further processing.

Abstract: An object of present invention is to provide an optical waveguide element that suppresses damage to an optical waveguide element by a pyroelectric effect due to a reinforcement substrate. Provided is an optical waveguide element in which an optical waveguide substrate is bonded to a reinforcement substrate having an electro-optical effect via an adhesive layer, the optical waveguide substrate having an optical waveguide formed on a substrate having the electro-optical effect and having a thickness of 30 ?m or less, wherein a semiconductor layer is provided on a surface of the adhesive layer side of the reinforcement substrate.

Abstract: An optical modulator includes: a semiconductor chip; a waveguide in the semiconductor chip; a traveling wave electrode including an input portion and an output portion, to which a signal is applied for modulating light passing through the waveguide; a power supply line connected to the input portion via a first wire; and a termination resistor connected to the output portion via a second wire. Capacitance between the output portion and a grounding point is larger than capacitance between the input portion and the grounding point.

Abstract: An optical control element which has a thin plate having an electro-optical effect and a thickness of 10 ?m or less, optical waveguides formed in the thin plate, and a plurality of optical control portions for controlling light propagating through the optical waveguide, wherein, a portion between a plurality of optical control portions is connected by a control signal wiring line that includes any one of a coplanar waveguide type disposed only on a surface of the thin plate, a coplanar waveguide type disposed on the surface of the thin plate and a ground electrode disposed on a back surface thereof, or a micro strip line, for arrival times of light and electric signal set to be substantially the same.

Abstract: Provided is a thermo-optical phase shifter including a composite body having an optical waveguide formed by a core and a clad and having a ratio ? of a difference between a core refractivity and a clad refractivity against the core refractivity which is 4% or above and a heater attached to the optical waveguide. The composite body has: a bridge structure portion arranged along a substrate surface and separate from the substrate surface via a void; and a fixed portion which supports the bridge structure portion with respect to the substrate and is continuous to the both ends of the bridge structure portion. The bridge structure has a half-circle-arc shape in the plane along the surface of the substrate.

Abstract: An optical modulator structure can include a core region that comprises an optical transmission path having a refractive index that is modulated via electric charge introduced into the core region. A plurality of first vertical slabs comes into contact with and is spaced along a first side of the core region to provide a first path for the electric charge to/from the core region. A plurality of second vertical slabs come into contact with and is spaced along a second side of the core region, that is opposite to the first side, to provide a second path for the electric charge to/from the core region. Other structures and methods are disclosed.

Abstract: A driving circuit of a semiconductor optical amplifier type gate switch constituting a matrix optical switch is provided with an operation amplifier into which a driving signal is input and from which a current corresponding to the driving signal is output, an inductance element provided at an output terminal of the operation amplifier, and a circuit composed of a diode element and a resistor element connected in parallel and provided between the inductance element and the semiconductor optical amplifier.

Abstract: An optical modulation device includes: a crystal substrate having an electro-optic effect; an optical waveguide formed in the crystal substrate; an electrode formed on the crystal substrate, to apply an electric field to the optical waveguide; and a buried layer of low dielectric constant buried to avoid the optical waveguide, in at least one portion of a lower region of the electrode inside the crystal substrate, which is spaced from both of a front surface of the crystal substrate on which the electrode is formed and a rear surface thereof opposed to the front surface.

Abstract: New electro-optic (EO) phase modulator devices and geometries, as can be constructed using a transparent conductive component.

Abstract: In an optical modulator, an intermediate substrate is provided separate from a main substrate on which a plurality of optical modulation sections are provided in parallel, and signal lines corresponding to the optical modulation sections are formed on the intermediate substrate. The signal lines are connected to signal electrodes corresponding to the main substrate, and have electrical lengths that are different from each other. Furthermore, the propagation loss per unit length in the signal lines on the intermediate substrate is preferably less than the propagation loss per unit length in the signal electrodes on the main substrate. As a result, even if a plurality of optical modulation sections are arranged in parallel, and the input ends of the signal electrodes of the optical modulation sections are arranged side by side on one side face of the substrate, synchronized modulation light of a low noise at a wide band width can be output from the optical modulation sections.

Abstract: New circuit architecture for electro-optic modulator based on free-carrier dispersion effect is invented, in which the waveguide capacitor of the modulator is embed in the circuits and physically layout together with transistors, the switching of the modulator occurs in transistors, and as the result, the electro-optical modulation occurs in the waveguide capacitor. The invented modulator is not one physical device, it is actually a circuit. Several circuit design techniques are imported, leading to several new modulator circuits that have very high operation speed and very small power consumption. Several new waveguide capacitor structures are also invented that allow high efficient modulator circuits to be built.

Abstract: The invention relates to a device, system, and method for optimizing and altering electromagnetic frequency using Doppler shifts of electromagnetic radiation, and, in particular, optimizing frequency for application to photovoltaic devices and the like. The device comprises a crystal positioned in a channel undergoing a vibration, wherein an interaction between an incoming electromagnetic radiation and the vibration of the crystal optimizes a frequency of electromagnetic radiation.

Abstract: A new photonic integrated circuit in the form of an optical pulse-train generator utilizes a time-interleaved architecture. The circuit can generate multiple optical pulses sequentially from a single trigger pulse, with the timing and amplitude of each pulse determined by circuit design. The circuit has application in optical arbitrary waveform generation and ultrafast electro-optic modulation.

Abstract: The present invention provides optical devices that employ nonlinear optical effects for processing optical signals. For example, such an optical device can include a nano-sized interferometric component that provides an optical output signal via interference of two input signals subsequent to their asymmetric nonlinear phase accumulation. The interferometric element can have a variety of configurations, such as Sagnac, Mach-Zehnder or Michelson configurations.

Abstract: Provided is a small-size optical phase modulation element and an optical modulator using it. The optical phase modulation element includes a Plasmon waveguide having a clad made of a metal material having a complex dielectric constant having a negative real part in the used wavelength and a core formed by a dielectric metal material having a complex dielectric constant having a positive real part in the used wavelength. The Plasmon waveguide is connected to an optical waveguide including a clad and a core both having a complex dielectric constant having a positive real part. The core of the Plasmon waveguide and the core of the optical waveguide are formed, at least partially, of the same semiconductor material. The Plasmon waveguide has a function to phase-modulate the incident light when voltage is applied.

Abstract: The invention generally relates, in one aspect, to an interferometer system. The interferometer system includes a splitter/combiner element (SCE), a first bi-directional optical path, and a second bi-directional optical path.

Abstract: Thermo-optical devices providing heater recirculation in an integrated optical device are described. The thermo-optical devices include at least one waveguide having a non-linear path length in thermal communication with a thermal device. Methods of fabrication and use are also disclosed.

Abstract: An electromagnetic resonance device includes an input reflector, an output reflector, and a periodic dielectric medium (PDM) disposed between the input reflector and the output reflector. The input reflector and output reflector are configured to be reflective to radiation having a wavelength of interest. The PDM includes a periodic structure having a dielectric periodicity between a first surface and a second surface. The dielectric periodicity is configured with a negative refraction for the wavelength of interest. A first radiation is reflected by the input reflector toward the first surface of the PDM, passes through the PDM, and is focused on the output reflector as a second radiation. The second radiation is reflected by the output reflector toward the second surface of the PDM, passes through the PDM, and is focused on the input reflector as the first radiation.

Abstract: A novel electroabsorption modulator based on tuning the Fermi level relative to mid-gap states in a semiconductor. The modulator includes a semiconductor waveguide that has an input port and an output port. Between the input port and the output port is a section of the waveguide that functions as an electroabsorptive region. Adjacent to the electroabsorptive region are electrical contacts. In operation by adjusting voltages on the electrical contacts, the quasi-Fermi level in the electroabsorptive region of the semiconductor waveguide is brought above or below mid band-gap electronic states. As these states transition between occupancy and vacancy, the absorption coefficient for optical radiation in the electroabsorptive region of the semiconductor changes.

Abstract: Provided is a semiconductor optical device, which has a buried heterostructure structure and is formed in a structure capable of reducing a parasitic capacitance to further improve characteristics thereof, and also provided are an optical transmitter module, an optical transceiver module, and an optical transmission equipment. The semiconductor optical device includes a modulator portion for modulating light input along an emitting direction and radiating the modulated light, the modulator portion including: a mesa-stripe structure, which includes an active layer and extends in the emitting direction; and a buried layer provided adjacent to each side of the mesa-stripe structure, in which a distance between a lower surface of the buried layer and a lower surface of the active layer is 20% or more of a distance between the lower surface and an upper surface of the buried layer.

Abstract: An optical modulator according to the present invention is configured at least by a semiconductor layer subjected to a doping process so as to exhibit a first conductivity type, and a semiconductor layer subjected to a doping process so as to exhibit a second conductivity type. Further, in the optical modulator, at least the first conductivity type semiconductor layer, a dielectric layer, the second conductivity type semiconductor layer, and a transparent electrode optically transparent in at least a near-infrared wavelength region are laminated in order.

Abstract: A polarization-tracking device having a waveguide grating that serves as a polarization splitter and an optical fiber-to-waveguide coupler. The polarization-tracking device also has an optical mixing circuit configured to receive light from the waveguide grating and a control circuit for tuning the optical mixing circuit. Based on an optical feedback signal received from the optical mixing circuit, the control circuit can configure the latter to produce two optical output signals that represent, e.g., two independently modulated polarization components of a polarization-multiplexed optical input signal or two principal states of polarization of an optical input signal that has been subjected to polarization-mode dispersion. Certain embodiments of the polarization-tracking device lend themselves to convenient implementation in a photonic integrated circuit and are configurable to provide endless polarization control.

Abstract: An optical waveguide device includes: a substrate having an electro-optical effect; an optical waveguide section formed on the substrate; and a plurality of modulating electrodes for modulating optical waves propagating in the optical waveguide section. The optical waveguide section branches into two parts in the propagating direction of the optical waves, thus forming the two main optical waveguides, and each of the main optical waveguides branches into two parts in the propagating direction of the optical waves, thus forming the two sub optical waveguides. The two main optical waveguides constitute a main Mach-Zehnder type optical waveguide, and the two sub optical waveguides are incorporated into the main Mach-Zehnder type optical waveguide to constitute a sub Mach-Zehnder type optical waveguide. A heat conduction suppressing zone is defined on a portion of the substrate disposed between two opposite sub Mach-Zehnder type optical waveguides.

Abstract: The invention provides a semiconductor optical modulator including a two-step mesa optical waveguide having a first clad layer (101); a mesa-like core layer (102) formed over the first clad layer (101); and a second clad layer (103) formed into a mesa shape over the core layer (102), and having a mesa width smaller than that of the core layer (102). The two-step mesa optical waveguide includes a multi-mode optical waveguide region to which an electric field is applied or into which an electric current is injected, and a single-mode optical waveguide region to which the electric field is not applied and into which the electric current is not injected. When the mesa width of the core layer in the multi-mode optical waveguide region is defined as Wmesa1, and the mesa width of the core layer in the single-mode optical waveguide region is defined as Wmesa2, Wmesa1>Wmesa2 is satisfied.

Abstract: An electronic device in which a signal electrode has a bent portion. Earth electrodes are formed with the signal electrode between. A width of a gap at the bent portion between the signal electrode and each earth electrode is narrower than a width of a gap at both ends of the bent portion between the signal electrode and each earth electrode.

Abstract: The components are a lower clad layer (102), a first silicon layer (103) that is formed on the lower clad layer (102) as a single body made of silicon of a first conduction type and has a slab region (105) that is disposed at a core (104) and on both sides of the core (104) and connects to the core, a concave section (104a) that is formed in the top surface of the core (104), and a second silicon layer (109) of a second conduction type that is formed inside the concave section (104a) with an intervening dielectric layer (108) to fill the inside of the concave section (104a).

Abstract: A high-index contrast waveguide component is presented, which is based on the fast changing of the transmission properties of an optical waveguide by applying electric voltages, or by embossing electric currents. The waveguide consists of a high-refractive waveguide core surrounded by a low-refractive surrounding material, which at least area by area has electro-optical properties. By applying a voltage to completely or partially optically transparent electrodes, an electric field is generated having a strong overlap with the optical mode, being in interaction with it, and therefore changing the transmission properties of the waveguide. The transparent electrodes or supply line areas are laminar, connected at low resistance with conductor paths of high conductivity by means of structures continually repeated along the propagation direction. Thus, it is possible for example to very fast load the capacity being effective between the electrodes, and to thus achieve a high electric band width.

Abstract: A device includes a resonator capable of supporting a plasmon mode, a gain structure arranged to couple energy into the resonator, and a memristive layer arranged to provide an interaction with the plasmon mode. An electric signal applied to the memristive layer can change the interaction and change a resonant frequency of the plasmon mode.

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.