26 results about "Nonlinear waveguide" patented technology

A chip-scale mode-locked laser including a cavity including a gain medium for amplifying signal electromagnetic radiation (signal) through stimulated emission, the signal comprising a signal wavelength; and a passive or active mode-locking device to enforce pulse formation in the laser. The mode-locking device includes a thin-film waveguide having a thickness on the order of the signal wavelength so as to confine and guide the signal along the thin-film waveguide, and a material comprising a second-order nonlinear susceptibility to enable active or passive mode-locking of the signal. The mode-locking device leads to generation of pulses of the signal outputted from the mode-locked laser.

A chip-scale mode-locked laser including a cavity including a gain medium for amplifying signal electromagnetic radiation (signal) through stimulated emission, the signal comprising a signal wavelength; and a passive or active mode-locking device to enforce pulse formation in the laser. The mode-locking device includes a thin-film waveguide having a thickness on the order of the signal wavelength so as to confine and guide the signal along the thin-film waveguide, and a material comprising a second-order nonlinear susceptibility to enable active or passive mode-locking of the signal. The mode-locking device leads to generation of pulses of the signal outputted from the mode-locked laser.

The invention belongs to the technical field of nonlinear optics, and discloses a method and a structure for realizing nonlinear waveguide quasi-phase matching. A plurality of groups of micro-nano structures are formed on the nonlinear waveguide along the waveguide propagation direction, each group of micro-nano structures comprises one or more air holes, the micro-nano structures are utilized to cause relative phases between different wavelength modes to generate jump, phase differences caused by phase mismatch are compensated, and quasi-phase matching is realized. The phase matching scheme provided by the invention is applicable to all nonlinear materials and waveguides, and has the advantage of high universality.

A semiconductor laser and a photonic nonlinear circuit chip are integrated together. The nonlinear circuit chip may include a nonlinear waveguide configured or controlled to enable sum-frequency generation, difference-frequency generation, second-harmonic generation, parametric amplification, or other nonlinear processes. Coupling between the semiconductor laser and the nonlinear circuit may be optimized by mode-matching, while back-reflections are minimized by diverting the reflections so that optical isolators are not needed. The integration of the semiconductor laser and the nonlinear photonic circuit chip enables nonlinear optical processing using a compact and scalable platform in a flexible manner that is compatible with different types of semiconductor lasers and different operation regimes. An additional input is provided so users can input an optical signal into the photonic chip for processing therein. In some examples, the photonic chip is configured with pump resonators, such as racetrack resonators. Method and device examples are described herein.

A nonlinear wave mixing system with grating assisted phase matching is provided. The system includes a pump laser and a nonlinear waveguide. The pump laser is used to generate pump light at a select wavelength. The nonlinear waveguide is configured to generate produced light from the pump light that is directed into the nonlinear waveguide. The nonlinear waveguide includes at least one backward grating that is configured to diffract the produced light in a backward direction relative to a direction the produced light travels in the nonlinear waveguide to reach the backward grating. The backward grating having a grating momentum that generates counter-propagating phase matching in the produced light.

Bright entangled photon sources including an alignment-free, fiber-based, mechanically-rugged and generic interferometric module are disclosed. The inherent phase-stability of a Sagnac interferometer is deployed. High down-conversion efficiency of periodically poled nonlinear-waveguides is combined with the optical gain of semiconductor optical amplifiers and immunity of fiber optics. A single compact interferometric engine combines these attributes, allowing highly stable, integrable and bright polarization entangled-photon sources operating at room temperature. Using a minimum number of in-line optical parts, the compact module is based on a novel method that enhances the long-term stability and efficiency without compromising the entanglement quality. Besides energy entanglement, polarization entanglement is presented and set through the operational conditions. An optional periodically poled nonlinear waveguide can be hosted to achieve the desired spectral bandwidth and photons generation rate. The result is a zero-maintenance, lightweight, low-power consumption engine of compact and fully-integrable bright polarization-entangled photon sources.

A quantum EIT-based optical switch includes a first waveguide, linear or nonlinear, a separate nonlinear waveguide evanescently coupled to the first waveguide, and a pump coupled to the nonlinear waveguide. A quantum STIRAP-based optical transduction device, which includes an auxiliary, intermediate spectral state for the quantum signal that aids efficient transduction of the quantum signal from the input spectral state to the output spectral state in a single device.

The invention belongs to the technical field of quantum information, and relates to a non-detection photon imaging system based on a single optical fiber integrated nonlinear waveguide. Comprising a continuous tunable pumping laser source, an optical amplifier, an adjustable optical attenuator, a first beam splitter, a first adjustable optical delay line, a first polarization controller, a second polarization controller, a first optical circulator, a nonlinear straight waveguide, a second optical circulator, a first optical filter, a second optical filter, a third optical filter, a fourth optical filter, a third optical circulator, a second adjustable optical delay line and an optical absorption terminal. The system comprises a first light collimator, a first lens, a three-dimensional scanning platform, a second lens, a second light collimator, a second beam splitter, a third polarization controller, a fourth polarization controller, a first single-photon detector, a second single-photon detector and a coincidence measurement unit. Compared with a traditional non-detection photon imaging system, quantum imaging of a transparent object can be achieved only through half of resource expenditure, and robustness is provided for the imaging system through all-fiber integrated configuration.

The application relates to a waveguide loss measurement method based on double-channel detection, which is used for accurately obtaining the linear loss coefficient of a nonlinear waveguide to be measured. Pump light, probe light and auxiliary laser are combined and injected into the waveguide to be measured to trigger a four-wave mixing effect to generate idler light; then, the waveguide output light is split into two paths through a light splitting element, and the idler light signal and the auxiliary laser signal are extracted as a measurement channel and a reference channel; the waveguide temperature is adjusted to stabilize the idler light power, and a linear interval of the probe light and the idler light power is obtained through fitting; the probe light power is fixed in the interval, a noise compensation factor is generated by using the average power and the instantaneous power of the auxiliary laser, the idler light power is corrected in real time, and finally the waveguide loss is calculated based on the corrected data. The method realizes real-time noise cancellation through double channels, combines parameter locking and linear interval screening, greatly improves the measurement stability and precision, and adapts to the loss detection requirements of various nonlinear waveguides.

The application provides a chip-on nonlinear amplification gain waveguide structure, which comprises, in sequence, an input waveguide, a first mode converter, a second mode converter, a nonlinear waveguide, a third mode converter and a fourth mode converter; a first signal light is input from the input waveguide to the fourth mode converter, is converted and output as a second signal light by the fourth mode converter, is input from the fourth mode converter to the first mode converter, is converted and output as a third signal light by the second mode converter, is input from the second mode converter to the third mode converter, and is converted and output to an output waveguide by the third mode converter. The application adopts a mode circulation type nonlinear gain amplification waveguide structure composed of multiple mode conversion devices, improves the space utilization of the chip-on waveguide, increases the action length of the optical field and the waveguide, thereby improving the generation efficiency of the nonlinear effect in a unit area, and realizing the effect of amplification gain.

The application discloses an AlGaAs second-order nonlinear and linear optical waveguide integrated monolithic and a manufacturing method thereof. x Ga 1‑x As composition; the surface of the epitaxial layer is used to manufacture a photoetching mask, and then the Bragg upper reflection layer is etched to form a ridge waveguide structure comprising a second-order nonlinear waveguide region and a second-order linear waveguide region; the second-order nonlinear waveguide region is used to manufacture a photoetching mask, and then the Bragg lower reflection layer of the second-order linear waveguide region is etched to complete the manufacturing. The application can realize seamless monolithic integration of AlGaAs optical nonlinear waveguide and linear waveguide, and provides a simple and high-integration chip manufacturing method for the fields of nonlinear optics and integrated quantum optics.

The invention relates to a waveguide loss measurement method based on dual-channel detection, which is used for accurately acquiring a linear loss coefficient of a nonlinear waveguide to be measured. Firstly, pump light, probe light and auxiliary laser are combined and injected into a waveguide to be detected, and a four-wave mixing effect is triggered to generate idler frequency light; splitting the waveguide output light into two paths through a light splitting element, and extracting an idler frequency light signal and an auxiliary laser signal as a measurement channel and a reference channel; adjusting the waveguide temperature until the idle frequency optical power is stable, and fitting to obtain a linear interval between the probe light and the idle frequency optical power; and fixing the detection light power in the interval, generating a noise compensation factor by using the average power and the instantaneous power of the auxiliary laser, correcting the idle frequency light power in real time, and finally calculating the waveguide loss based on the corrected data. According to the method, real-time noise counteracting is achieved through two channels, parameter locking and linear interval screening are combined, the measurement stability and precision are greatly improved, and the loss detection requirements of various nonlinear waveguides are met.

The present application belongs to the technical field of quantum and biological imaging, and particularly relates to an oral biological imaging device based on quantum entanglement phase. The present application utilizes continuous laser pumping nonlinear waveguide to generate energy-time entangled photon pairs, separates signal photons from idler photons through an optical filter; places the oral biological sample to be measured in a non-balanced interferometer, measures the Franson interference between signal photons and idler photons with or without biological samples, obtains two different phase interference curves, and calculates the entanglement phase difference. The position of the sample to be measured is changed through a two-dimensional scanning platform, the Franson interference is performed, and the entanglement phase difference at different positions is obtained. The phase differences are combined to obtain the quantum phase image of the sample. The present application can realize high-precision imaging of microstructures; all components of the present application can come from mature optoelectronic devices, and have the advantages of miniaturization, integration, practicality and the like, and open up a new way for the development of quantum precision measurement and life science.

The invention provides an all-fiber broadband high-compression-degree vacuum compression state light source based on double-pass amplification, and relates to the technical field of quantum optics. Laser emitted by a laser passes through an isolator and then enters a beam splitter; after passing through the beam splitter, most of the laser enters the frequency doubling module to generate pump light; a small part of laser is used as background light for subsequent detection; pump light is input from a first port of the circulator, output from a second port of the circulator and enters the compressed light generation module, the compressed light generation module is a nonlinear waveguide crystal, the incident end face of the nonlinear waveguide crystal is plated with a high-transmittance film for the pump light, and the transmittance is larger than 99%. The emergent end face is plated with a high-transmittance film for compressed light and a high-reflection film for pump light, and the transmittance of the high-transmittance film is gt; the reflectivity of the high-reflectivity film is gt; and the pump light reflected back by the emergent end face enters the nonlinear waveguide crystal again, is emergent from the incident end face, enters the second port of the circulator and is output from the third port, so that the separation of the pump light and the compressed light is realized.

The application belongs to the technical field of quantum information, and relates to a non-probing photon imaging system based on a single optical fiber integrated nonlinear waveguide, which comprises a continuously tunable pump laser source, an optical amplifier, an adjustable optical attenuator, a first beam splitter, a first adjustable optical delay line, a first polarization controller, a second polarization controller, a first optical circulator, a nonlinear straight waveguide, a second optical circulator, first, second, third and fourth optical filters, a third optical circulator, a second adjustable optical delay line, an optical absorption terminal, a first optical collimator, a first lens, a three-dimensional scanning platform, a second lens, a second optical collimator, a second beam splitter, a third polarization controller, a fourth polarization controller, a first single-photon detector, a second single-photon detector and a coincidence measurement unit. Compared with a traditional non-probing photon imaging system, the application can realize quantum imaging of a transparent object by using only half of the resource consumption, and the all-optical fiber integrated configuration provides robustness for the imaging system.

In some embodiments, a device for generating mid-infrared radiation is provided. The device may include a thin film quadratic nonlinear waveguide formed on a mid-infrared transparent cladding by a thin film material of a predetermined film thickness, the waveguide having a predetermined etch depth and a predetermined top width. At least one of the predetermined film thickness, the predetermined etch depth, and the predetermined top width may be tuned for the device to generate a coherent idler wave as a mid-infrared radiation from a fixed pump wave and a tunable signal wave.

The invention belongs to the field of nonlinear optical devices, and particularly discloses a nonlinear waveguide. The nonlinear waveguide comprises a sub-wavelength grating waveguide and a two-dimensional material, wherein the two-dimensional material is located on the surface of the sub-wavelength grating waveguide. According to the technical scheme, the evanescent field of the waveguide is enhanced through the sub-wavelength grating structure, then the two-dimensional material with the high nonlinear effect is integrated in the evanescent field area, the two-dimensional material and the evanescent field generate stronger interaction, then the nonlinear effect is further enhanced, and compared with the mode that the surface of a common waveguide is directly combined with the two-dimensional material, the non-linear effect is further enhanced. The nonlinear waveguide provided by the invention has a higher nonlinear effect.

The invention provides a metal dielectric interlayer nonlinear waveguide and application thereof, the waveguide structure is formed by alternately stacking metal layers and dielectric layers, and the dielectric layers are located between the two metal layers. A cylindrical cavity is dug in the midpoint area of the dielectric layer to form a specific cavity structure. According to the design, through interaction of the metal layer and the dielectric layer and combination of the light field local enhancement effect of the cavity structure, the intensity of the nonlinear optical effect is remarkably improved. The waveguide structure has the advantages of being high in integration level, low in loss and high in conversion efficiency, can be widely applied to the fields of ultrafast optics, optical communication, optical sensing and the like, and provides a new solution for miniaturization and high performance of nonlinear optical devices.

The invention relates to an optical system for converting the frequency, and thereby the wavelength, of a single photon and a method for converting the frequency of a single photon by difference-frequency generation (DFG). Further, the invention relates to a frequency converter. A single photon with a first wavelength (λp) and a laser irradiation with a second wavelength (λi) are arranged for combining in a multiplexer and transmitted to a nonlinear waveguide. The multiplexer comprises two input waveguides for receiving the single photon and the laser irradiation and is combining them in one of the waveguides from where it is transmitted to the nonlinear waveguide. In the nonlinear waveguide, the single photon interacts with the laser irradiation and the material of the nonlinear waveguide, so as to frequency convert the single photon from the first wavelength (λp) to a third wavelength (λs). The multiplexer and the nonlinear waveguide are structurally integrated on a compact platform, preferable a photonic integrated circuit (PIC), by being grown on the platform or bonded to the platform.

The application discloses a three-dimensional multiplexing signal on-chip all-optical wavelength conversion device based on a single nonlinear waveguide. The wavelength conversion device mainly comprises a transverse magnetic mode demultiplexer, a transverse electric mode demultiplexer, a polarization beam splitter and a multimode nonlinear waveguide. The application utilizes wavelength multiplexing technology, mode multiplexing technology and polarization multiplexing technology, and combines the dispersion engineering of a silicon-based waveguide, so that a multi-wavelength-dual-polarization-dual-mode hybrid multiplexing signal realizes wideband and efficient all-optical wavelength conversion in a multimode nonlinear optical waveguide. Under the participation of pump light, the signal light is converted into idle frequency light carrying the same data as the signal light. The application can greatly improve the transmission capacity of a communication system, reduce the number of wavelength converters in a communication network, improve the flexibility of wavelength routing, and has the advantages of simple structure, high efficiency, small area, easy integration and expansion, and the like. The application can be widely applied to the field of super-large-capacity all-optical signal processing in an all-optical communication network.

This invention discloses an on-chip nonlinear waveguide mode conversion device and its fabrication method based on ferroelectric domain engineering. The device includes a Z-cut thin-film lithium niobate waveguide, which, from top to bottom, comprises a Z-cut thin-film lithium niobate, a silicon dioxide layer, and a silicon substrate. The Z-cut thin-film lithium niobate layer has a two-dimensional ferroelectric domain structure with periodically alternating positive and negative domains. The electrode structure for fabricating this two-dimensional ferroelectric domain structure consists of n+1 groups of comb-shaped electrodes arranged alternately, with the electrodes insulated from each other. Each group of comb-shaped electrodes is periodically arranged, with the electrode width being 1 / 4 of the polarization period, and n being the number of nodes in the target transverse electric field. This invention utilizes high-voltage electric field polarization technology and semiconductor fabrication processes to fabricate a Z-cut thin-film lithium niobate waveguide with a two-dimensional ferroelectric domain structure on a thin-film lithium niobate material platform, thereby solving the nonlinear conversion problem from the fundamental mode to the second harmonic higher-order mode of the waveguide, and also exhibits scalability.

The invention discloses an integrated mid-infrared TDLAS (tunable diode laser absorption spectroscopy) detection device and method, and relates to the technical field of laser spectrum. Comprising a local device and a far-end device, the local device comprises a controller, a DFB1 laser, a DFB2 laser and a detector, the DFB1 laser, the DFB2 laser and the detector are connected with the controller, the far-end device comprises a substrate, and the substrate is provided with a first nonlinear waveguide, a waveguide extension line, a filter and a second nonlinear waveguide which are sequentially connected. The DFB1 laser and the DFB2 laser are respectively connected with the first optical fiber, the first optical fiber is connected with the first nonlinear waveguide, the far-end device is connected with the second optical fiber through the second nonlinear waveguide, and the second optical fiber is connected with the detector. According to the invention, the integration degree is high, the detection sensitivity of the TDLAS technology is improved, and the cost is reduced.

The utility model provides an identical photon pair light source, which comprises a pump laser, a nonlinear waveguide, a filter, a wavelength division multiplexer and a single photon frequency shifter, can output a plurality of identical photon pairs with different wavelengths through a single nonlinear waveguide, and is simple and compact in structure, high in integration level, wide in spectral range of the generated identical photon pairs, and high in efficiency. And multiple wavebands and multiple application scenes, such as a quantum communication waveband, a quantum measurement waveband and a quantum optical experiment waveband, are supported.

A c-axis preferred orientation zinc oxide magnesium ridge waveguide and its fabrication method, the method comprising: preferentially oriented Zn along the c-axis l‑x Mg x A strip-shaped masking layer is formed on the O thin film, where 0 ≤ x ≤ 0.3; and under the protection of the masking layer, the c-axis Zn is preferentially oriented using a dry etching technique. 1‑x Mg x The O thin film is etched to form a ridge waveguide structure. The Zn obtained in this invention... l‑x Mg x O-ridge waveguides can be used in passive and active devices such as nonlinear waveguides, optical couplers, waveguide modulators, waveguide switches, and waveguide lasers, and have broad application prospects in fields such as integrated optics and optical interconnects.

This invention provides a broadband phase-matching control method, system, device, and storage medium, belonging to the field of integrated photonics technology. The method includes: acquiring dispersion parameters and pump parameters, calculating phase mismatch parameters at each frequency point; calculating the optimal nonlinear action length at each frequency point and establishing a mapping relationship between frequency and optimal nonlinear action length; constructing a spatial action length scheduling function and converting it into a control parameter distribution for the corresponding nonlinear action process, thereby scheduling and controlling the nonlinear action process in the nonlinear waveguide; during the execution of the scheduling control, acquiring the output parameters for each frequency channel and updating the spatial action length scheduling function to output the multi-frequency channel output results. This invention achieves adaptive scheduling control of the multi-frequency channel nonlinear action process under broadband conditions, thereby improving the consistency and stability of the output of each frequency channel.

An optical tensor core includes a device platform, a broadband, phase-locked, optical frequency comb generator, an array of electro-optic (EO) modulators, wherein a vector, {Xj} and a matrix, {Aij} are encoded onto optical comb mode fields, and a non-linear waveguide, wherein a sum frequency generation (SFG) operation occurs directly on the optical comb mode fields so as to realize a multiply-accumulate (MAC) operation between the vector {Xj} and the matrix {Aij}. An integrated system and related methodologies and applications are disclosed.