Abstract: In an optical transmission system including a plurality of optical transmitting units and a relay device, the plurality of optical transmitting units include a frequency modulation conversion unit that converts an input signal into a frequency modulation signal through frequency modulation conversion processing, a multiplexing unit that multiplexes monitoring signals with different frequencies with the frequency modulation signal, and an optical modulation unit that converts the frequency modulation signal that is an electric signal in which the monitoring signals are multiplexed into optical signals having different wavelengths, and the relay device includes a photoelectric conversion unit that acquires a combined signal obtained by combining optical signals having different wavelengths from each other and converts the combined signal into an electric signal, and a measuring unit that measures transmission quality of the plurality of monitoring signals included in the electric signal.

Abstract: There is provided an optical power feeding system including: an optical power feeding unit; and a plurality of drop units configured to be able to receive light from the optical power feeding unit as an input, branch the input light, and output branched light, in which, the optical power feeding unit includes a power-feed light generating unit that outputs power-feed light, and the drop unit includes: an optical splitter that branches the power-feed light into first branch light and second branch light and outputs the second branch light to another drop unit; a photoelectric conversion unit that performs photoelectric conversion of the first branch light; and a branch ratio control unit that is driven by electricity generated by the photoelectric conversion and controls a branch ratio that is a ratio between the first branch light and the second branch light.

Abstract: A branch ratio setting system includes: a branch ratio control unit; and a plurality of drop units configured to be able to receive an optical signal from the branch ratio control unit, and configured to branch and output the received optical signal, and the branch ratio control unit outputs light to the plurality of drop units via an optical fiber to measure characteristics of the optical fiber, and outputs a branch ratio determination signal to each of the plurality of drop units via the optical fiber based on the measured characteristics of the optical fiber, and the drop unit includes an optical splitter connected to the optical fiber and having a variable branch ratio and a branch ratio setting unit that sets the branch ratio of the optical splitter based on the branch ratio determination signal input via the optical fiber.

Abstract: An optical switch is provided which is capable of driving control by the same FPGA and the same driving circuit configuration, and hence is capable of driving at a high speed and a low consumption power. The optical switch of the present disclosure is a 1×N optical switch having a structure in which with respect to an optical switch, a driving circuit of the optical switch is integrated in the vicinity of a control electrode of the optical switch. The optical switch includes a plurality of 2×2 optical switches and N optical gates. Different bias voltages (Vb) are set between the optical switches and the optical gates, and a driver for the 2×2 optical switch of the driving circuit and a driver for the optical gate are of the same circuit form.

Abstract: An optical device includes a rib waveguide that is a thin-film lithium niobate (LN) crystal, a buffer layer that is laminated on the rib waveguide, and an electrode that applies voltage to the rib waveguide. The buffer layer includes a thick-film part that is laminated on a rib of the rib waveguide, and thin-film parts that are laminated on slabs of the rib waveguide, where the slabs are located on both sides of the rib, and that have smaller thicknesses than a thickness of the thick-film part.

Abstract: A method, includes providing a wafer including a first surface grating extending over a first area of a surface of the wafer and a second surface grating extending over a second area of the surface of the wafer; de-functionalizing a portion of the surface grating in at least one of the first surface grating area and the second surface grating area; and singulating an eyepiece from the wafer, the eyepiece including a portion of the first surface grating area and a portion of the second surface grating area. The first surface grating in the eyepiece corresponds to an input coupling grating for a head-mounted display and the second surface grating corresponds to a pupil expander grating for the head-mounted display.

Abstract: The instant disclosure is directed toward integrated-optics-based composite phase controllers that include at least one thermo-optic (TO) phase controller and at least one stress-optic (SO) phase controller, each of which is configured to affect the phase, or other propagation characteristic, of a light signal travelling through a surface waveguide. The SO phase controller can induce a small phase change quickly, while the TO phase controller can slowly induce a larger phase change. Embodiments are particularly well suited for use in waveguide-based resonant elements, such as ring resonators, spectral filters, and the like. Furthermore, photonic systems comprising one or more composite phase controllers can be developed, such as wavelength-tunable lasers for applications such as LiDAR, chemical/biological sensing, medical diagnostics, and optical communications.

Abstract: An ultra-long sub-wavelength grating as an optical antenna for optical phased arrays includes a top structure and a bottom structure which are vertically stacked. The bottom structure is made of a material with a refractive index lower than a refractive index of the top structure. The top structure is made of a material with a refractive index higher than that of the bottom structure. A strip waveguide is disposed in the middle of the top structure. subwavelength blocks are disposed periodically on two sides of the straight strip waveguides. The invention has the following beneficial effects. The structure could increase the effective length of the grating; uniform near field distribution can be achieved by controlling the positions of the subwavelength blocks. The structure is simpler with lower fabrication requirements and lower cost.

Abstract: An electro-absorption modulator (EAM) is configured to include an on-chip AC ground plane that is used to terminate the high frequency RF input signal within the chip itself. This on-chip ground termination of the modulation input signal improves the frequency response of the EAM, which is an important feature when the EAM needs to support data rates in excess of 50 Gbd. By virtue of using an on-chip ground for the very high frequency signal content, it is possible to use less expensive off-chip components to address the lower frequency range of the data signal (i.e., for frequencies less than about 1 GHz).

Abstract: An electro-optical intensity modulation apparatus has a non-linear optical substrate and electrodes. The non-linear optical substrate is provided with a first branch waveguide, a second branch waveguide, a first channel waveguide and a second channel waveguide thereon. The first channel waveguide and the second channel waveguide are disposed between the first branch waveguide and the second branch waveguide, and the first channel waveguide and the second channel waveguide are branched from the first branch waveguide and converged at the second branch waveguide.

Abstract: The optical modulator includes a lower cladding layer formed on a substrate, a core formed on the lower cladding layer, and an upper cladding layer formed on the core. The core is made of an InP-based semiconductor having a bandgap corresponding to a desired wavelength. Refractive indexes of the lower cladding layer and upper cladding layer are equal to or less than a refractive index of InP.

Abstract: Methods and systems for selectively illuminated integrated photodetectors with configured launching and adaptive junction profile for bandwidth improvement may include a photonic chip comprising an input waveguide and a photodiode. The photodiode comprises an absorbing region with a p-doped region on a first side of the absorbing region and an n-doped region on a second side of the absorbing region. An optical signal is received in the absorbing region via the input waveguide, which is offset to one side of a center axis of the absorbing region; an electrical signal is generated based on the received optical signal. The first side of the absorbing region may be p-doped. P-doped and n-doped regions may alternate on the first and second sides of the absorbing region along the length of the photodiode. The absorbing region may comprise germanium, silicon, silicon/germanium, or similar material that absorbs light of a desired wavelength.

Abstract: An optical data communication system includes an optical power supply and an electro-optical chip. The optical power supply includes a laser that generates laser light at a single wavelength. A comb generator receives the light at the single wavelength and generates multiple wavelengths of continuous wave light from laser light at the single wavelength. The multiple wavelengths of continuous wave light are provided as light input to the electro-optical chip. The electro-optical chip includes at least one transmit macro that receives the multiple wavelengths of continuous wave light and that modulates one or more of the multiple wavelengths of continuous wave light to generate modulated light signals that convey digital data.

Abstract: An apparatus such as an optical modulator includes a buried oxide layer is disposed on a substrate. A microring resonator and an optical waveguide are disposed on the buried oxide layer and within a bonded semiconductor layer. The optical waveguide is optically coupled to the microring resonator and inputs a first optical wave into the microring resonator. An oxide layer is deposited on top of the optical waveguide and the microring resonator. A set of electrodes is disposed adjacent to the microring resonator, and in response to an electrical signal, the set of electrodes modulates the first optical wave into a modulated optical wave of transverse magnetic polarization within the microring resonator and outputs the modulated optical wave to the optical waveguide.

Abstract: An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.

Abstract: Optical devices and their fabrication from thin film lithium niobate are provided. In some embodiments, an optical device includes a substrate and an optical waveguide disposed on the substrate. The optical waveguide comprises lithium niobate. The optical waveguide has a central ridge extending laterally along the substrate. A pair of electrodes is disposed on opposite sides of the central ridge of the optical waveguide.

Abstract: A waveguide structure for use in a balanced push-pull Mach Zehnder modulator. The waveguide structure comprises a plurality of layers. The layers comprise, in order: an insulating or semi-insulating substrate; an lower cladding layer; an waveguide core layer; and an upper cladding layer. The lower cladding layer, waveguide core layer, and upper cladding layer are etched to form: a signal waveguide and a ground waveguide, which are connected via the lower cladding layer; and a signal line and a ground line, each located adjacent to the respective waveguide, and each connected to the respective waveguide via one or more respective resistive structures connected in the plane of the lower cladding layer.

Abstract: An on-chip interferometer and a spectrometer including the interferometer are provided. An on-chip interferometer includes a waveguide for propagation of an optical signal including an input waveguide; at least two interferometer arms having one or more slot waveguides; and an output waveguide; wherein the input waveguide is split into the at least two interferometer arms which are recombined into the output waveguide; and a control mechanism configured for controlling a relative time delay between optical signals propagating in the two interferometer arms by modifying one or more slot widths of one or more of the slot waveguides; and wherein the relative time delay is at least 1, 2, 5, or at least 10 fs or at least one optical period of the longest optical wavelength of the optical signal.

Abstract: An optical modulation method and device capable of stably generating an optical signal including a zero-intensity state among four states required for phase-time coding scheme by a nested modulator, is provided. A controller controls the phase difference generated by the phase shifter and an intensity and a magnitude of phase modulation provided by each of the first modulator and the second modulator to change an output lightwave of the nested modulator between four constellation points (S1-S4) on IQ plane. A first constellation point (S4) of the four constellation points has an intensity of 0, a second constellation point (S1) has a relative intensity of 1, each of a third constellation point (S2) and a fourth constellation point (S3) has a relative intensity ranging from 0 to 1, and the third and the fourth constellation points has a phase difference of 90 degrees.

Abstract: A semiconductor optical modulator includes a modulation region and a non-modulation region. A first width of a first ground electrode in the non-modulation region is larger than a second width of the first ground electrode in the modulation region. A third width of a second ground electrode in the non-modulation region is larger than a fourth width of the second ground electrode in the modulation region. In the non-modulation region, a first insulating layer is disposed between a first optical waveguide and a first traveling wave electrode and between a second optical waveguide and a second traveling wave electrode. For this reason, a bandwidth of the semiconductor optical modulator can be widened.

Abstract: An optical modulator is provided that is capable of preventing a short circuit at a step such as an annealing step in a manufacturing process, thereby improving the manufacturing yield.

Abstract: A fiber-optic switching system is provided which includes an optical fiber switch having first and second optical fiber portions and an electrically-controlled actuator. The first and second optical fiber portions are spaced apart with a gap between the portions that is sized to allow for light signal coupling between the optical fiber portions in a signal-passing state of the switch. The electrically-controlled actuator is coupled to transition the switch between the signal-passing state, where the light signal is allowed to pass between the optical fiber portions, and a signal-non-passing state, where the light signal is prevented from passing between the optical fiber portions. The electrically-controlled actuator includes an electroactive material exhibiting a physical change with change in an applied electrical field, where the physical change facilitates transitioning the optical fiber switch between the signal-passing and the signal-non-passing states.

Abstract: Structures for a polarizer and methods of fabricating a structure for a polarizer. A first waveguide core has a first tapered section, a second tapered section, and a section positioned along a longitudinal axis between the first tapered section and the second tapered section. The first tapered section and the second tapered section each narrow in a direction along the longitudinal axis toward the section. A second waveguide core has a first terminating end, a second terminating end, and a section that is arranged between the first and second terminating ends. The section of the second waveguide core is positioned either over or below the section of the first waveguide core.

Abstract: 3D graphene optical sensors, such as microstructure sensors and nanostructure sensors. The 3D optical sensors include one or more graphene panels shaped to surround an interior, open volume. Graphene plasmons couple across the interior, open volume. The 3D optical sensors can have a polygonal shape or a cylindrical shape.

Abstract: A touch switch includes a light-pervious plate, a first peripheral frame, a second peripheral frame and an electrical switch module. The light-pervious plate has a predetermined shape. The first peripheral frame corresponds in shape to the light-pervious plate. One side face of the first peripheral frame is coupled to one side face of the light-pervious plate. The second peripheral frame corresponds in shape to of the first peripheral frame. One side face of the second peripheral frame is coupled to another side face of the first peripheral frame. The electrical switch module corresponds in shape to the second peripheral frame. One side face of the electrical switch module is coupled to another side face of the second peripheral frame. The side face of the electrical switch module is provided with at least one light sensitive switch.

Abstract: Provided is an optical modulator which is small in optical loss, is small in a size, and is low in required voltage and is operable to perform high-speed operation. The optical phase modulator 100 comprises a rib-type waveguide structure 110 including: a PN junction 106 which is formed of Si and is formed in a lateral direction on a substrate; and an Si1-xGex layer 108 which is constituted of at least one layer and is doped with an impurity to a p-type and is superposed on the PN junction 106 so as to be electrically connected to the PN junction 106. The rib-type waveguide structure 110 has a substantially uniform structure along a light propagation direction, and in a direction parallel with the substrate and perpendicular to the light propagation direction, a position of a junction interface 106a of the PN junction 106 is offset from a center of the Si1-xGex layer 108.

Abstract: A method of optical modulation in a non-resonant epsilon-near-zero (EMZ) plasmonic electro-optical modulator is provided. An optical carrier is injected into a waveguide optically coupled to a layer of transparent conductive material having an epsilon-near-zero (ENZ) wavelength. The transparent conductive material layer constitutes a portion of a capacitive structure that includes a gate dielectric layer. A time-varying bias voltage applied across the gate dielectric layer shifts the ENZ wavelength toward the carrier wavelength, and thereby impresses a phase modulation pattern on the carrier wave.

Abstract: An actively tunable optical filter can control the amplitude of reflected infrared light. The filter exploits the dependence of the excitation energy of plasmons in a continuous and unpatterned sheet of graphene, on the Fermi-level, which can be controlled by conventional electrostatic gating. An exemplary filter enables simultaneous modification of two distinct spectral bands whose positions are dictated by the device geometry and graphene plasmon dispersion. Within these bands, the reflected amplitude can be varied by over 15% and resonance positions can be shifted by over 90 cm?1. Electromagnetic simulations verify that tuning arises through coupling of incident light to graphene plasmons by a nanoantenna grating structure. Importantly, the tunable range is determined by a combination of graphene properties, device structure, and the surrounding dielectrics, which dictate the plasmon dispersion. Thus, the underlying design is applicable across a broad range of infrared frequencies.

Abstract: Various embodiments of a photonic integrated circuit (PIC) are described herein. A PIC, functioning as a coherent receiver, may include optical components such as an optical coupler, a directional coupler, a beam splitter, a polarizing beam rotator-splitter, a variable optical attenuator, a monitor photodiode, 90-degree hybrid mixer, and a waveguide photodiode. The PIC may also include electrical components such as an electrode, a capacitor, a resistor and a Zener diode.

Abstract: An optical beam spot size convertor is provided having a body. The body comprises a first optical waveguide having a first refractive index and a plurality of second optical waveguides each having a second refractive index higher than the first refractive index. The first optical waveguide is arranged to receive an input optical beam. The first optical waveguide is further arranged such that light from the input optical beam is coupled from the first optical waveguide into the plurality of second optical waveguides. The body further comprises an output optical waveguide and a reflective part coupled to the plurality of second optical waveguides and to the output optical waveguide. The reflective part is arranged to focus optical beams received from the plurality of second optical waveguides into a single optical beam which is directed to the output optical waveguide.

Abstract: Methods for increasing the degree of curing and/or reducing the volatile photoinitiator concentration in cured polymeric film, and particularly in cured polymeric films in a multilayered thin film encapsulation stack are provided. Also provided are highly crosslinked and/or low-outgassing thin polymeric films and encapsulation stacks made using the methods.

Abstract: Embodiments herein describe a photonic chip which includes a coupling interface for evanescently coupling the chip to a waveguide on an external substrate. In one embodiment, the photonic chip includes a tapered waveguide that aligns with a tapered waveguide on the external substrate. The respective tapers of the two waveguides are inverted such that as the width of the waveguide in the photonic chip decreases, the width of the waveguide on the external substrate increases. In one embodiment, these two waveguides form an adiabatic structure where the optical signal transfers between the waveguides with minimal or no coupling of the optical signal to other non-intended modes. Using the two waveguides, optical signals can be transmitted between the photonic chip and the external substrate.

Abstract: A steerable laser transmitter and situational awareness sensor uses a liquid crystal waveguide (LCWG) to steer a spot-beam onto a conical mirror, which in turn redirects the spot-beam to scan a FOV. The spot-beam passes through one or more annular sections of non-linearly material (NLM) formed along the axis and around the conical mirror. Each NLM section converts the wavelength of the spot-beam to a different wavelength while preserving the steering of the spot-beam. The LCWG may shape or move the spot-beam along the axis of the conic mirror to sequentially, time or time and spatially multiplex the spot-beam between the original and different wavelengths. This provides multispectral capability from a single laser source. The transmitter also supports steering the spot-beam at a wavelength at which the LCWG cannot steer directly.

Abstract: In an optical modulator 115 of an embodiment, an optical waveguide core 121 is configured from an n? type semiconductor region 134, a gate insulating film 136 on the n? type semiconductor region 134, and a p? type semiconductor region 137 on the gate insulating film 136. Further, a width W1 of the n? type semiconductor region 134 and a width W1 of the p? type semiconductor region 137 are equally formed and are layered without being shifted. Therefore, an optical modulator having stable optical characteristics can be provided.

Abstract: An arrayed waveguide grating multiplexer/demultiplexer includes an array of optical waveguides ordered in sequence from a shortest waveguide up to a longest waveguide, and identical phase shifters configured to be controlled by a same control signal. Each phase shifter increases/decreases an optical path of an optical waveguide by the same quantity based on the control control signal.

Abstract: A cycloidal diffractive waveplate (50) comprising first and second substrate layers (52, 54), a liquid crystal layer (60C, 60H) provided between the first and second substrate layers, and transparent positive electrodes (56) and transparent negative electrodes (58) provided on the first substrate layer. The liquid crystal layer has a diffractive state (60C) in which the optical axes of the liquid crystal molecules are periodically rotated across a plane of the waveplate and a non-diffractive state (60H) in which the optical axes of the liquid crystal molecules are all orientated in the same direction in the plane of the waveplate. The electrodes (56, 58) are arranged in an alternating series, such that when an electric voltage is applied to the electrodes an electric field is produced in the plane of the waveplate and the liquid crystal layer is switched from the diffractive state to the non-diffractive state. A method of manufacturing the cycloidal diffractive waveplate is also provided.

Abstract: An arrayed waveguide grating multiplexer/demultiplexer includes an array of optical waveguides ordered in sequence from a shortest waveguide up to a longest waveguide, and identical phase shifters configured to be controlled by a same control signal. Each phase shifter increases/decreases an optical path of an optical waveguide by the same quantity based on the control signal.

Abstract: A display device includes a first electrode, a second electrode, a third electrode, a lyophobic layer, a first liquid, and a second liquid, where the lyophobic layer is lyophobic to the second liquid. A method of driving the display device includes: providing a first potential difference between the first electrode and the third electrode to thereby cause the first liquid to begin moving toward the second electrode; providing a second potential difference between the second electrode and the third electrode while reducing the first potential difference to thereby cause the first liquid to move toward the first electrode; and removing the second potential difference to thereby cause the first liquid to slow down in its movement toward the first electrode or to stop in its movement toward the first electrode.

Abstract: A distance measuring device includes a light source emitting light, and an integrated electro-optic modulator arranged such that the emitted light passes through an optical waveguide of the electro-optic modulator in a first direction before being emitted from the distance measuring device, and after being reflected from a target passes through the electro-optic modulator in a second direction which is opposite to the first direction. The forward electro-optic response of a modulating region of the electro-optic modulator is the same as the backward electro-optic response, and a center of gravity of the modulation is independent of modulation frequency.

Abstract: An optical device including: a waveguide of refractive index na for carrying at least one mode of at least one wavelength, and at least one resonator with a resonant wavelength. The resonator has a mode volume of less than ten cubic resonant wavelengths. In use light in the waveguide is vertically coupled into the at least one resonator, and the waveguide and resonator(s) are arranged to provide wave-vector matching between at least one mode of the resonator and at least one mode of the waveguide.

Abstract: An optical part 20A includes a supporting body 1, an optical material substrate 2, an electrode provided on the supporting body 1, and a resin adhesive layer 4 adhering the electrode 7 and optical material substrate 2. The electrode 7 includes a chromium film 7c contacting the resin adhesive layer 4 and a gold film 7b provided between the chromium film 7c and supporting body 1.

Abstract: A method of manufacturing a frequency tunable terahertz transceiver including two separate distributed feedback lasers manufactured in one substrate, includes forming a lower clad layer on the substrate, forming an active layer on the lower clad layer, forming an upper clad layer on the active layer. And interposing first and second diffraction grating layers between the upper clad layers. A diffraction grating is manufactured by etching the first and second diffraction grating layers. The active layer is integrated into a passive waveguide. An electrode is formed on the upper clad layer.

Abstract: A lens element includes a first surface, a second surface, at least one first communicating lens portion on the first surface, at least one second communicating lens portion on the second surface, and a first deflecting surface for deflecting optical signals between the at least one first communicating lens portion and the at least one second communicating lens portion. The lens element further includes a first testing lens portion, a second testing lens portion, a second deflecting surface, and a third deflecting surface. The second deflecting surface and the third deflecting surface deflect a detecting light converged by the first testing lens portion at a predetermined angle so that the detecting light passes out of the lens element through the second testing lens portion.

Abstract: A photonic microresonator incorporates a localized heater element within a section of an optical bus waveguide that is in proximity to the resonator structure. The application of an adjustable control voltage to the heater element provides a localized change in the refractive index value of the bus waveguide, compensating for temperature-induced wavelength drift and maintaining a stabilized value of the microresonator's resonant wavelength.

Abstract: A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces metalized with first metallic layers formed thereon, and encapsulated with a dielectric encapsulation material such as for example epoxy. The first metallic layers are exposed through the encapsulation via encapsulation concavities which have a known contour profile, such as a Rogowski edge profile. Second metallic layers are then formed to line the concavities and come in contact with the first metal layer, to form profiled and metalized encapsulation concavities which mitigate enhancement points at the edges of electrodes matingly seated in the concavities. One or more optical waveguides may also be bonded to the substrate for coupling light into the photo-conductive wafer, with the encapsulation also encapsulating the waveguides.

Abstract: A tunable Radio Frequency (RF) filter device includes a tunable optical source configured to generate an optical carrier signal, and a modulator coupled to the tunable optical source and configured to modulate the optical carrier signal with an RF input signal. The tunable RF filter device may also include first and second optical waveguides coupled to the modulator and having first and second dispersion slopes of opposite sign, and an optical-to-electrical converter coupled to the first and second optical waveguides and configured to generate an RF output signal with a frequency notch therein based upon the tunable optical source.

Abstract: An apparatus with either a graphene sheet or an epsilon-near-zero layer sandwiched in a waveguide structure and a tuning device. The tuning device is configured to selectively control application of at least first and second gate voltages across the waveguide structure. The graphene sheet has a first dielectric constant which is zero and the waveguide structure operates at a first absorption state and a first propagation distance with application of the first voltage by the tuning device and has a second dielectric constant and the waveguide structure operates at a second absorption state and a second propagation distance with application of the second voltage. The second dielectric constant is larger than the first dielectric constant, the second absorption state is smaller than the first absorption state, the second propagation distance is longer than the first propagation distance, and the second voltage which is zero or smaller than the first voltage.

Abstract: A tunable Radio Frequency (RF) filter device includes a tunable optical source generating an optical carrier signal, and a modulator coupled to the tunable optical source and modulating the optical carrier signal with an RF input signal. The tunable RF filter device may include first and second optical waveguide paths coupled to the modulator and having first and second dispersion slopes of opposite sign from each other, one or more of the first and second optical waveguide paths comprising an optical splitter and combiner pair therein, and an optical-to-electrical converter coupled to the first and second optical waveguide paths and generating an RF output signal with a frequency notch therein based upon the tunable optical source.

Abstract: A tunable Radio Frequency (RF) filter device includes a tunable optical source configured to generate an optical carrier signal, and a modulator coupled to the tunable optical source and configured to modulate the optical carrier signal with an RF input signal. The tunable RF filter device may also include first and second optical waveguides coupled to the modulator and having first and second dispersion slopes of opposite sign, and an optical-to-electrical converter coupled to the first and second optical waveguides and configured to generate an RF output signal with a frequency notch therein based upon the tunable optical source.

Abstract: A surface-plasmon-polaritons (SPPs) tunable optical resonant ring filter that includes an SPPs waveguide, an SPPs tunable directional coupler, and an SPPs tunable resonant ring. The tunabilities of the resonant frequency, the resonant depth, and the filtering bandwidth are achieved by tuning the loss and transmission phase of the resonant ring and the coupling ratio of the directional coupler. Since the metal core layer of the SPPs waveguide is capable of multiplexing electro-optical signals, the SPPs tunable optical resonant ring filter can be used not only in an integrated optics system, but also in an integrated electro-optics hybrid system.