The method for manufacturing the heterojunction circuit according to one embodiment of the present disclosure comprises depositing a first electrode on at least a part of a waveguide, moving a semiconductor comprising a second electrode at a lower end thereof onto the first electrode, and depositing a third electrode on an upper end of the semiconductor, wherein the waveguide and the semiconductor comprise different materials. Additionally, the moving step further comprises generating microbubbles by supplying heat to at least a part of the semiconductor, moving the semiconductor on the first electrode by moving the generated microbubbles, and removing the microbubbles by positioning the semiconductor on the first electrode.

Disclosed a photonic motor that comprises a first optical waveguides arrangement, including at least one first optical resonator lying in a first plane and forming a static part of the motor; at least a second optical waveguides arrangement, including at least one second optical resonator lying in a second plane parallel to the first plane and forming a moving part of the motor, wherein an evanescent-wave coupling of optical modes is established between at least one first optical resonator of the first optical waveguides arrangement and at least one second optical resonator of the second optical waveguides arrangement, the first and second optical resonator being adapted to guide at least one resonant symmetric mode at a predetermined first wavelength or at least one resonant anti-symmetric mode at a predetermined second wavelength or at least a combination or superposition of at least one resonant symmetric mode at a predetermined first wavelength.

Back scattering in an optical waveguide at an operating wavelength is controlled by adjusting an optical phase of light propagating in the waveguide at one or more locations along the waveguide. A portion of the back scattered light is tapped off near an input port and coupled into a photodetector. A controller detects changes in the photodetector signal and adjusts an optical phase tuner configured to control the optical phase of light in the waveguide at the selected location or locations. The optical phase tuner may be configured to vary the refractive index of at least a portion of the waveguide.

A modulated light source includes a reflective semiconductor optical amplifier including a mirror at a first end of the reflective semiconductor optical amplifier, a modulator configured to modulate a central wavelength, a first mirror configured to reflect light transmitted by the modulator, an optical filter disposed between a second end of the reflective semiconductor optical amplifier and the modulator, and a second mirror configured to reflect part of incoming light and to transmit the other part of the incoming light. The reflective semiconductor optical amplifier, the optical filter, and the second mirror configure a Fabry-Perot laser. The first mirror is configured to feed light emitted from the Fabry-Perot laser back to the Fabry-Perot laser, and the modulated light source is configured to select light corresponding to one of longitudinal modes oscillated by the Fabry-Perot laser, to modulate the selected light, and to output the modulated light.

A method for forming an optical fiber having at least one of a microresonator and a coupler integrated therein is described. The method includes providing an optical fiber having a light guiding core. modifying at least one region of the optical fiber using a laser, immersing the optical fiber having the at least one region as modified inside an etchant that selectively etches the at least one region as modified to generate at least one of a microresonator and a coupler integrated in the optical fiber, and removing the optical fiber from the etchant. The optical fiber as removed from the etchant may include the at least one of the microresonator and the coupler. The method may further include heating the optical fiber using, for example, a CO.sub.2 laser or other heating apparatus, to smoothen surface irregularities of at least one of the microresonator and the coupler.

An optical waveguide element includes: a cladding portion made of silica-based glass; and a plurality of optical waveguides positioned in the cladding portion and made of silica-based glass in which ZrO.sub.2 crystal particles are dispersed. The optical waveguide element is a planar lightwave circuit. The plurality of optical waveguides configure an arrayed waveguide grating element.

The invention relates to a method for producing a reference frequency f. According to the invention, the use of a first optical resonator (3a; 24) and of a second optical resonator (25) is provided, wherein the first resonator (3a; 24) has a first resonator mode having a first frequency f1 and the second resonator (25) has a second resonator mode having a second frequency f2, wherein the frequencies of the two resonator modes are functions of an operating parameter BP and assume the values f1 and f2at a specified value BP.sub.0 of the operating parameter such that f1(BP.sub.0)=f1 and f2(BP.sub.0)=f2 apply, wherein the resonators (3a; 24, 25) are designed in such a way that the respective first derivatives of the frequencies f1(BP), f2BP) with respect to BP or at least respective difference quotients around BP.sub.0 correspond within a deviation of at most 0.1%, wherein light of the first frequency f1 is stabilized to the first frequency f1 by means of the first resonator and light of the second frequency f2 is stabilized to the second frequency f2 by means of the second resonator, and wherein the difference between the stabilized frequencies f1 and f2, f=|f1f2|, is determined in order to obtain the stabilized reference frequency f.

Embodiments of the present invention relate to a microring resonator control method and apparatus. The method includes: receiving an instruction, where the instruction is used to configure an operating wavelength of a microring resonator; determining whether the operating wavelength of the microring resonator is less than or equal to a center wavelength of a channel spectrum; and when the operating wavelength of the microring resonator is less than or equal to the center wavelength of the channel spectrum, configuring thermode power of the microring resonator based on a spacing between the operating wavelength and a first wavelength; or when the operating wavelength of the microring resonator is greater than the center wavelength of the channel spectrum, configuring thermode power of the microring resonator based on a spacing between the operating wavelength and a second wavelength.

Coupling modulation of an optical resonator employs a variable modal index to provide modulation of optical signal coupling. A coupling-modulated optical resonator includes an optical resonator having a coupled portion and a bus waveguide having a modulation section adjacent to and coextensive with and separated by a gap from the coupled portion. The modulation section is to modulate coupling of an optical signal between the optical resonator and the bus waveguide according to a variable difference between a modal index of the bus waveguide modulation section and a modal index of the optical resonator coupled portion.

A device for guiding and absorbing electromagnetic radiation, the device including: absorbing means for absorbing the electromagnetic radiation; and a coupled to the absorbing means for guiding the electromagnetic radiation to the absorbing means, wherein the waveguide and the absorbing means are formed from a structure including a first cladding layer, a second cladding layer over the first cladding layer, and a quantum-well layer between the first and second cladding layers, the quantum-well layer being formed of a material having a different composition to the first and second cladding layers, wherein the thickness and the composition of the quantum-well layer is optimised to provide an acceptable level of absorption of electromagnetic radiation in the waveguide while providing an appropriate band gap for absorption of the electromagnetic radiation in the absorbing means.