25 results about "Optical nonlinearity" patented technology

The exponential growth in deep learning models is challenging existing computing hardware. Optical neural networks (ONNs) accelerate machine learning tasks with potentially ultrahigh bandwidth and nearly no loss in data movement. Scaling up ONNs involves improving scalability, energy efficiency, compute density, and inline nonlinearity. However, realizing all these criteria remains an unsolved challenge. Here, we demonstrate a three-dimensional spatial time-multiplexed ONN architecture based on dense arrays of microscale vertical cavity surface emitting lasers (VCSELs). The VCSELs, coherently injection-locked to a leader laser, operate at gigahertz data rates with a 7T-phase-shift voltage on the 10-millivolt level. Optical nonlinearity is incorporated into the ONN with no added energy cost using coherent detection of optical interference between VCSELs.

The application discloses a kind of diffractive light neural network computing systems and methods for realizing pure optical nonlinearity, belong to photonic computing and artificial intelligence hardware technical field.Its system includes coherent light source, linear light computing unit, nonlinear light activation unit and optical detection unit arranged in order along optical path, wherein linear light computing unit is programmable phase modulation using spatial light modulator, nonlinear light activation unit is programmable binary amplitude modulation using digital micromirror device, and both are directly coupled to form pure optical computing path without photoelectric conversion on optical path.Its method trains neural network through customized loss function, drives nonlinear activation function output to binary convergence, and maps the parameters obtained by training into phase map and binary mask respectively and loads to hardware.The application realizes true all-optical nonlinear computation, with the advantages of high energy efficiency, extremely low delay, compact structure and strong parallel processing capability.

The invention discloses an optical nonlinear activator chip based on a graphene photoelectric device and a preparation method. Belongs to the technical field of photoelectric devices and optical signal processing. The chip comprises a detector optical path and a modulator optical path, a substrate is made of a standard SOI material, and the chip structurally comprises an optical coupling module, a waveguide, a graphene detector part and a graphene modulator part. The graphene detector and the modulator are integrated on the same chip, the detector is used for converting an input optical signal into a voltage signal, then the voltage signal is input into the modulator to modulate continuous light, and an optical signal after nonlinear conversion is output and used for a nonlinear activation unit of an optical neural network. Compared with a traditional nonlinear activator of a silicon-based integrated photon chip, the method gives full play to the advantages of excellent photoelectric property and easy integration of graphene, has the advantages of high integration level, high speed, low power consumption and the like, and has better compatibility with a silicon-based optoelectronic process.

The present invention provides an on-chip photonic circuit for generation of a polarization-entangled photon-pair state by utilizing the optical nonlinearities in a novel configuration comprising dual micro-resonators, with nearly degenerate transverse-electric- and transverse-magnetic-polarized cavity resonances for the two resonators coupled in series to a common bus waveguide, wherein, the pump laser and the generated signal and idle photons can be coupled in and out the photonic circuit.

An optical parametric multi-pass apparatus for generating laser radiation through optical parametric amplification or generation converts pump radiation into signal and idler radiation. It includes a multi-pass device with multiple mirror elements arranged to provide several beam paths from an input section to an output section of the device. The input section receives pump radiation, and the output section delivers signal radiation as the generated laser output. At least one optically nonlinear crystal is positioned within the device to enable the parametric process using the pump radiation. The mirror configuration ensures multiple passes of the beam paths through the crystal. The device is further designed to filter along the beam paths so that idler radiation is suppressed after at least one pass. A corresponding laser apparatus and method for generating laser radiation are also described.

An optical nonlinearity measurement method according to the present disclosure utilizes photon pair generation through a spontaneous four-wave mixing process, to observe photon pairs using an optical waveguide loaded with a two-dimensional material. Compared with the Z-scan method, the influence of free carriers on nonlinear refractive indexes is only indirect. With a parameter being the length of the attached two-dimensional material in the optical waveguide direction, a theoretical value of the coincidence rate of the photon pairs based on the coupled wave equation is fitted to a measured value of the coincidence rate of the photon pairs. For the coincidence rate of the photon pairs, the theoretical value based on the coupled wave equation is fitted to the measured value in a state reflecting the structure of the optical waveguide loaded with the two-dimensional material, and nonlinear coefficients γ1 and γ2 at that time are obtained.

The present invention provides scalable manufacturing approaches to add compound semiconductor (CS) materials and devices to large-diameter substrate platforms. The method includes forming a CS buffer layer overlying the large-diameter substrate wafer, then a stop etch layer, and finally a device layer structure for high carrier mobility, optical gain or absorption, or optical nonlinearity. This device wafer is then bonded, topside down, to a photonics substrate platform. The underlying substrate is removed with grinding, polishing, or etching processes. Some of the CS layers, including the buffer and the stop etch layer, may be removed thereby leaving only the final device layer. This final layer may be patterned to form waveguides or device structures; may be exposed to ion implantation steps to form p-n junctions; and may be subjected to other common fabrication steps to form devices. These device structures may also be encapsulated and addressed through top-level metal contacts and vias.

The embodiment of the invention provides a frequency conversion device based on a lithium niobate ridge waveguide on an insulator and a preparation method, and belongs to the field of integrated optical, nonlinear optical and optoelectronic devices. The device comprises a silicon substrate layer, a silicon dioxide buffer layer, an x-cut lithium niobate film layer and a silicon dioxide cladding from bottom to top, a ridge waveguide with width periodically changing is arranged on the x-cut lithium niobate layer, and light in the waveguide is propagated in the y-axis direction. The waveguide with the width periodically changing is prepared on the lithium niobate film, quasi-phase matching is achieved, and therefore the second harmonic conversion efficiency is greatly improved. By changing the period of the waveguide, second-order nonlinear phase matching conditions under different wavelengths, such as phase matching conditions of second harmonic generation, sum frequency generation and difference frequency generation, can be met. Correspondingly, according to the preparation method, the waveguide structure with the periodically changed width can be formed through a single etching process, and a complex ferroelectric domain inversion step is not needed. The preparation method has the advantages of simple process, controllable morphology and flexible design.

A laser system (1) comprises a laser radiation source (7) for providing a pulsed laser radiation (9), wherein the pulsed laser radiation comprises laser pulses (11) having a pulse energy in the range of 1 mJ to 100 J or in the range of 10 mJ to 1 J and a pulse duration in the range of 10 fs to 5 ps or in the range of 500 fs to 1.5 ps. The laser system (1) further comprises an optical system (3) for spectral broadening of the pulsed laser radiation (9). The optical system (3) comprises: - a first polarization setting optics (19) setting a circular polarization state (17B) of the pulsed laser radiation (9), and - a multi-pass cell (5) having at least two mirrors (25A, 25B) through which the pulsed laser radiation (9) passes forming a plurality of intermediate focus regions (29), wherein the multi-pass cell (5) is filled with a filling gas (5A) having an optical nonlinearity, wherein the filling gas (5A) enables spectral broadening of the pulsed laser radiation (9) in the intermediate focus regions (29). Further, a pressure of the filling gas (5A) is set in a pressure range in which there is an ionization behavior of the filling gas (5A) in the regime of multiphoton ionization, and a focus diameter (d) of the intermediate focus regions (29) is set such that the pulsed laser radiation (9) passes through the multi-pass cell (5) without ionization of the filling gas (5).

Optical assembly for generating the second and third harmonic frequencies of a laser beam using two optically nonlinear crystals (C1 and C2) placed in a temperature-controlled environment. The first optically nonlinear crystal (C1) converts the fundamental harmonic frequency to the second harmonic, while the second optically nonlinear crystal (C2) converts the fundamental and second harmonics to the third harmonic. The system includes beam intensity attenuation mechanisms using a first half-wave plate (HWP1) and first and second polarizers (P1, P2) that direct the beam according to the user's requirements. Motorized linear shifts (T1, T2) provide switching between harmonic frequency generation modes. Different cuts of the optically nonlinear crystals (C1 and C2) allow for optimization of phase matching and conversion efficiency. This assembly is designed for highly accurate and flexible generation of harmonic laser beams with wide industrial applications, especially in laser micromachining.

The invention relates to a method and an arrangement for the nonlinear spectral broadening of temporally incoherent or partially coherent optical pulses of a pulsed laser beam, which have a pulse duration not limited by bandwidth. In one embodiment of the method, the pulsed laser beam is split into two partial beams, which are spectrally shifted relative to each other by a frequency difference Δf. The spectrally shifted partial beams are then at least partially superimposed such that they interfere in the time domain during or after superposition and form at least one modulated pulsed laser beam, the pulses of which exhibit a temporal modulation of intensity with a period Δt = 1 / Δf.The pulses of the modulated pulsed laser beam are then spectrally broadened by self- or cross-phase modulation in an optically nonlinear medium, achieving a large spectral broadening through this modulation. This method and setup are particularly advantageous for IFE driver lasers.

The invention discloses a method for predicting optical soliton time domain evolution in an optical fiber based on an improved width learning system. The method comprises the following steps: constructing a width learning system, wherein the width learning system adopts a flattened network structure to realize structure horizontal expansion of feature nodes, enhanced nodes and the like; improving a width learning system, wherein the improvement comprises improving an incremental learning algorithm action range to synchronously adjust multiple layers of nodes so as to enable the system to learn more data features; the training system is suitable for optical soliton prediction. According to the method, the network structure can be dynamically updated in the training process, complex retraining is avoided, and the training efficiency and the prediction accuracy are effectively improved. In addition, the method utilizes a ridge regression algorithm to quickly solve pseudo-inverse from a hidden layer to an output layer, so that the training time is remarkably shortened, and quick and accurate prediction is realized. The method can be applied to rapid prediction of other optical nonlinear evolution processes, and a new thought is provided for application of the flattening network in physical field modeling and the optical field.

The application discloses a kind of optical deep neural network chips based on time domain, belong to optical computing technical field.A kind of optical deep neural network chips based on time domain, including sequentially connected: optical signal input area, input data modulator area, convolution weight modulator area, first optical nonlinear unit area, pooling modulator area, fully connected weight modulator area, second optical nonlinear unit area, high-speed photoelectric detector area and time domain integrator area.Optical deep neural network chip includes the three kinds of functions of convolution, pooling and fully connected in classic convolutional neural network, covers input layer, hidden layer and output layer in depth network;Multiple optical nonlinear unit area cascades are used to realize multilayer depth optical neural network, and large-scale high-throughput optical computing is realized by time dimension.Multiple layers of optical deep neural network computing are realized, and are suitable for artificial intelligence big model training, semantic segmentation, image recognition and medical instrument modeling imaging and other optical computing fields.

The invention discloses a photon neuromorphic autonomous navigation method and system, and the method comprises the steps: obtaining environment point cloud data through a laser radar, and constructing an environment state vector after sector division and feature extraction; a pulse neural network is used for dynamic time sequence reasoning, core calculation is achieved through an optical linear calculation module and an optical nonlinear activation module, the optical linear calculation module completes high-speed and low-power-consumption linear operation through an MZI interferometer, and the optical nonlinear activation module generates nonlinear pulse response through a DFB-SA laser array; and finally, the output pulse signal is converted into a robot control instruction. The pulse neural network and the photon calculation are combined, the advantages of high parallelism and low power consumption of the photon calculation and the high energy efficiency characteristic of the pulse neural network are fully played, the real-time performance, the energy efficiency ratio and the environmental adaptability of the navigation system are remarkably improved, and an efficient autonomous navigation solution is provided for the mobile robot.

An apparatus comprises: a plurality of linear optical elements, where each linear optical element is configured to apply a change in amplitude or phase of an optical wave interacting with that linear optical element; and a plurality of nonlinear optical elements, where each nonlinear optical element is configured to apply a change in an amplitude or a phase of an optical wave interacting with that nonlinear optical element, where the change in an amplitude or a phase is a nonlinear function of an amplitude or a phase of the optical wave; wherein one or more nonlinear optical elements are arranged to interact with an optical wave between successive interactions of the optical wave with two linear optical elements; wherein the plurality of linear optical elements is configured to sort optical waves into one or more optical modes of a sorted mode distribution.

The invention relates to an optical nonlinear arithmetic device and a testing system and method of the optical nonlinear arithmetic device, the optical nonlinear arithmetic device comprises a tunable laser and a nonlinear arithmetic unit, the nonlinear arithmetic unit works in a light amplification mode, and the tunable laser and the nonlinear arithmetic unit are connected through an optical fiber. The tunable laser is used for emitting optical signals with adjustable wavelength and power, the nonlinear arithmetic unit is used for carrying out nonlinear transformation on the optical signals and outputting nonlinear optical signals, and the nonlinear optical signals and the optical signals are in a nonlinear activation function relation. The optical nonlinear arithmetic device has the advantages of high speed and low nonlinear optical power threshold.

The embodiment of the application discloses a large-core glass optical fiber and a manufacturing method, the large-core glass optical fiber comprises: a multi-component core layer glass and a cladding glass, wherein: the cladding glass is cylindrical, and the cladding glass is provided with a through hole in the length direction; the multi-component core layer glass is cylindrical, and the shape of the multi-component core layer glass matches the shape of the through hole of the cladding glass, and the multi-component core layer glass is arranged in the through hole of the cladding glass. By arranging the multi-component core layer glass and the cladding glass, the manufacturing process is simple, the multi-component core layer glass is arranged in the cladding glass, the core radius and the cladding radius of the glass optical fiber can be improved, the stimulated Brillouin threshold of a high-power single-frequency narrow-line-width optical fiber laser is improved, and the problems of various optical nonlinear effects and unstable laser output modes of the existing optical fiber are solved.

The invention relates to an optical nonlinear operation device, an optical nonlinear operation assembly and a preparation method of a fluorescent material. The optical nonlinear arithmetic device comprises a fluorescent material layer and a reflecting layer, wherein the fluorescent material layer covers one side of a reflecting surface of the reflecting layer; the fluorescent material layer comprises a fluorescent material, the fluorescent material layer is used for absorbing part of incident laser emitted by the incident light source, and the service life of the fluorescent material is 1 nanosecond to 50 microseconds; the reflecting layer comprises a plane reflecting mirror and is used for reflecting the rest of incident laser emitted by the incident light source except for part of the incident laser. By adopting the device provided by the invention, the calculation effect of optical calculation can be improved.

The invention discloses a method and a device for regulating and controlling a high-order Poincare spherical beam, and provides a method for effectively regulating and controlling the high-order Poincare spherical beam with complex vector polarization distribution in multiple dimensions such as angular momentum, light intensity distribution, polarization state and the like by using a nonlinear optical crystal based on a nonlinear effect of second harmonic. And different phase matching conditions in the second harmonic generation process are set, so that the regulation and control results of the second harmonic of the high-order Poincare spherical beam are enriched. According to the method and the device, a good effect is achieved during nonlinear regulation and control of the high-order Poincare spherical beam, the structure is simple, the cost is low, regulation and control of multi-dimensional optical properties are achieved, and the method and the device are suitable for design of optical nonlinear polarization imaging elements.

A nonlinear optical microdevice array that enables low energy and massively parallel nonlinear optical control with incoherent light. Optical computing has been a goal long sought after, because it allows for massively parallel information processing. The major roadblock has been the difficulty to achieve efficient optical nonlinearity that is required in controlling one light by another light beam. A semiconductor pn junction and electro-optical modulator (e.g., liquid crystal or micromirror array) are integrated at a single pixel scale, to achieve artificial optical nonlinearity that is highly parallel (with millions of pixels), extremely energy efficient (at sub picojoule level), and compatible with incoherent LED light sources.

A new architecture for a photoelectric logic gate is disclosed. This architecture is energy-efficient, realizes a strong optical nonlinearity, and can be directly realized in modern photonics foundries without process modifications, enabling immediate application to current-day photonic systems. The new architecture utilizes the integration of current onto the intrinsic capacitance of the optical modulator.

A device for optically imaging a scene (SZ) has at least one optical detector (S1) and an optical arrangement which is arranged in front of the optical detector (S1) and by means of which the scene (SZ) can be imaged in a focal plane (F) of the optical arrangement. The detector surface of the optical detector (S1) is arranged outside the focal plane (F), and the optical arrangement has an amplitude mask or phase mask (M) which enables improved algorithmic reconstruction of a sharp image of the scene (SZ) from a blurred image captured by the detector (S1). In the device, in an alternative an optically non-linear filter (N) is additionally arranged in the region of the focal plane (F) and, in the case of incident optical radiation with an intensity above a threshold intensity, changes its optical properties in such a way that it blocks or at least attenuates said radiation. By means of said device, an optical sensor system is realized which has an improved protective effect against interference radiation, in particular incident laser radiation, with virtually unchanged overall size.

The application discloses an optical phase detection method and device using SPR to enhance nonlinear effect, and the method comprises the following steps: forming interference by coherent light beams with different phases to generate a fundamental frequency light interference fringe image; and the interference fringe image is incident on a Kretschmann structure with a gold film on a slope at a resonance angle to excite surface plasmon resonance, reduce the intensity of reflected light, and improve nonlinear conversion effect; and the fundamental frequency light in the reflected light is filtered out, and interference fringe images or power data of high-order harmonics are collected to perform interference phase detection. The application converts phase difference information into optical nonlinear information, uses surface plasmon resonance to enhance nonlinear effect, completes enhancement of nonlinear effect, and the phase detection capability is amplified by the square and the cube, so that the contrast of bright and dark fringes of the interference image is enhanced, and the precision and resolution of phase measurement are improved.

The application discloses a kind of photonic neural morphology autonomous navigation method and system, the method obtains environment point cloud data by laser radar, constructs environment state vector after sector division and feature extraction;Dynamic timing inference is carried out using pulse neural network, and its core calculation is realized through optical linear calculation module and optical nonlinear activation module: the former is completed by MZI interferometer linear operation of high speed, low power consumption, and the latter generates nonlinear pulse response using DFB-SA laser array;Finally, the output pulse signal is converted into robot control instruction.The application combines pulse neural network with photonic computing, fully gives the high parallelism and low power consumption advantage of photonic computing, and the high energy efficiency characteristics of pulse neural network, significantly improves the real-time performance, energy efficiency ratio and environmental adaptability of navigation system, and provides an efficient autonomous navigation solution for mobile robot.

The present application relates to a kind of all-optical nonlinear neural network systems based on linear system, belong to optical neural network technical field.Solve the bottleneck problem that optical neural network relies on nonlinear material or photoelectric conversion to realize nonlinear operation.Techinical scheme includes input module, and input signal is loaded in annular resonant cavity resonance wavelength detuning amount;Coupling module controls interlayer weight;Neuron module passes through multilayer annular resonant cavity linear transmission signal;Output module loads output signal in probe light power.Input and output signal are loaded in different physical quantities, so that linear system realizes nonlinear function.Affordable effect includes breaking through optical nonlinear operation bottleneck, significantly reduce system complexity and energy consumption, enhance compatibility and practicality, improve parallel computing efficiency and system scalability.