78 results about "Nonlinear medium" patented technology

The invention discloses a method, a system, equipment and a medium based on a multi-composite ultrasonic penetration technology, and the method comprises the steps: generating high-frequency fundamental ultrasonic waves through a piezoelectric transducer array, and adjusting the frequency range to match the acoustic impedance characteristic of target soil; first, second and third harmonics are generated through the induction of a nonlinear medium in the fundamental wave propagation process, the phases of the harmonics are adjusted to realize coherent superposition, and the fundamental wave and the first, second and third harmonics are guided into a composite waveguide device for focusing and delay compensation to form a high-energy composite wave beam; a pulse interval is adjusted by adopting an intermittent emission strategy so as to inhibit energy attenuation in the soil; reflected wave spectrum components are monitored through an embedded acoustic sensor array, and driving parameters are dynamically adjusted; and residual ultrasonic energy is captured and fed back to a driving circuit to form a closed-loop energy utilization system. By integrating multi-order harmonic resonance and a dynamic frequency tuning technology, efficient transmission and deep penetration of ultrasonic energy in a complex medium are realized.

An optical computation system includes a light source configured to produce a pump beam, an optical modulator configured to modulate the pump beam based on the modulation mask to generate a modulated beam, a non-linear medium configured to convert a portion of the modulated beam to a second harmonic (SH) beam and to produce an output including the SH beam and an unconverted portion of the pump beam, and a dichroic mirror configured to receive the output of the non-linear medium and to decouple the SH beam and the unconverted portion of the pump beam, a detector configured to detect a first optical power of the unconverted portion of the pump beam and to detect a second optical power of the SH beam, and a controller configured to generate an updated modulation mask based on the first and second optical powers for transmission to the optical modulator.

The classical channel employs a transmit laser and classical modulator. The quantum channel employs a nonlinear medium and spontaneous parametric down conversion producing quantum entangled signal and idler photon pairs which are encoded. The classical and quantum channels are combined to define a propagated hybrid signal. The receiver splits the hybrid signal on basis of wavelength into classical and quantum channels. The quantum receiver employs optical parametric amplification, supplied with energy from a second harmonic generation device synchronized to the classical carrier wavelength. A photodetector and extracts a quantum message from the quantum signal.

A device useful as a spectrometer or a sensor, comprising a source of a short electromagnetic pulses at a first wavelength and having a full width at half maximum in a range of 1 femtosecond-1 nanosecond; a sample holder in which the short pulses interact with the sample in the sample holder so as to form an output signal comprising a background residual of the short pulses and a sample response signal in the time domain, and an amplifier comprising nonlinear medium. The nonlinear medium comprises an input for receiving the output signal and a pump pulse at a second wavelength, and a second-order nonlinearity configured for a nonlinear process selectively amplifying the sample response signal, for example by temporally overlapping the pump pulse and the sample response signal.

A wireless communication system includes a transmitter, a plurality of passive substantially linear medium portions including one or more first portions and a second portion, one or more passive substantially nonlinear medium portions disposed proximate the substantially linear medium portions, and for each first portion, a dielectrically lossy or magnetically lossy first material disposed on the first portion. When the transmitter transmits first and second radio waves, the substantially linear and nonlinear medium portions receive the first and second radio waves and generate first and second signals propagating therein, where at least one intermodulation signal is generated in the one or more substantially nonlinear medium portions from the first and second signals, and the one or more first materials reduces the generation of the at least one intermodulation signal by at least 2 dB.

The invention relates to the field of ultrafast laser, and discloses a nonlinear femtosecond pulse energy self-stabilizing device. Comprising a nonlinear self-phase modulation module, a reflector, a grating, a lens and a filter which are arranged in sequence, and the nonlinear self-phase modulation module, the reflector, the grating, the lens and the filter form a light beam transmission path; the nonlinear self-phase modulation module comprises a conical lens, a low-dispersion lens and a nonlinear medium; the reflecting mirrors are reflecting mirrors with consistent reflection spectrums; the grating is used for expanding a spectrum carrying energy fluctuation information in a spatial domain to form frequency domain spatial distribution related to energy; the lens is used for focusing or collimating the light beam expanded by the grating; the filter is a liquid crystal filter and is used for dynamically setting a filtering range; abnormal disturbance in the light path is identified by using the generative adversarial network, and a compensation strategy is generated; the abnormal disturbance comprises sudden mechanical vibration and nonlinear coefficient mutation at the initial stage of medium damage.

The invention discloses an on-chip spontaneous frequency conversion light source based on a semiconductor nanowire-silicon nitride waveguide structure, and belongs to the technical field of integrated optics and nonlinear optics. According to the light source, the high-nonlinearity characteristic of the semiconductor nanowire is utilized, and the semiconductor nanowire is embedded in the silicon nitride waveguide, so that the frequency up-conversion function which the silicon nitride waveguide does not have is realized. The light source structure comprises a silicon nitride waveguide serving as a light wave transmission channel, a semiconductor nanowire serving as a nonlinear medium core and a grating coupler integrated with the waveguide so as to realize efficient transmission of optical signals. The light source has the advantages of low power consumption, high integration level, easiness in butt joint with an existing optical fiber system and the like, and is suitable for an on-chip optoelectronic integrated system.

The application provides a nonlinear optical effect generation method, relates to the field of optoelectronic technology, and comprises the following steps: fixing and placing a polar ion crystal as a nonlinear medium, the polar ion crystal being a diatomic crystal or a polyatomic crystal with an optical phonon mode; using a modulated terahertz wave to excite a stimulated phonon polariton in the nonlinear medium, so as to enhance the nonlinear efficiency of signal light incident on the nonlinear medium; and adjusting the polarization angle and the incident angle of the signal light and / or the modulated terahertz wave, so as to generate a nonlinear optical effect. The application is based on the characteristics of the interaction between light and matter modulated by the stimulated phonon polariton, and the nonlinear polarizability is greatly improved by using the stimulated phonon polariton, so that the weak light nonlinear effect of most wavelengths of light can be realized efficiently; and the nonlinear optical effect has the advantages of high refresh rate, wide spectral response, low threshold and low power consumption.

The application discloses a phase-sensitive pre-amplification method based on an electro-absorption modulated laser, and is applied to a star-ground laser communication system receiving end. A distributed feedback laser in the electro-absorption modulated laser amplifies weak pump light after long distance transmission, and generates idler light under the nonlinear effect of a laser cavity; an electro-absorption modulator in the electro-absorption modulated laser detects phase error information between signal light, pump light and idler light, and constructs an optical injection phase-locked loop through a feedback loop, so that stable control of the three-wave phase relationship is realized. Under the phase stability condition, the output light of the electro-absorption modulated laser is fed into a later-stage nonlinear medium to complete phase-sensitive pre-amplification. The phase-sensitive pre-amplification method based on the electro-absorption modulated laser has the advantages of simple structure and easy integration, can realize pump light amplification, idler light generation and phase error suppression under the condition of weak pump light, and effectively improves the receiving sensitivity performance of the star-ground laser communication system.

The invention discloses a disc Mmyshev mode-locked laser, and belongs to the technical field of ultrafast laser. The disc Mmyshev mode-locked laser comprises a laser gain module, a first nonlinear medium, a second nonlinear medium, a first interference filter, a second interference filter, a dispersion compensation module, an output coupling mirror, a first concave reflecting mirror, a second concave reflecting mirror, a high reflecting mirror, a third concave reflecting mirror and a fourth concave reflecting mirror. According to the disc Mmyshev mode-locked laser, a Mmyshev filtering mechanism is introduced into the disc Mmyshev mode-locked laser, and mode-locked self-starting and ultra-short pulse output under the condition of high average power are achieved. The disc Mmyshev mode-locked laser does not need an SESAM or Kerr mode-locked medium, can obtain stable ultrashort pulses smaller than 100 femtoseconds, has high stability, self-starting, good beam quality and structural expandability, and is suitable for application fields such as precise micromachining and extreme ultraviolet lithography driving sources.

The invention discloses a satellite backbone network edge node all-optical data distribution method and system. The system comprises a pumping unit, a data processing unit, a high-nonlinearity medium module, a coupler and a demultiplexer. The backbone laser link is injected into the data processing unit; a first input port and a second input port of the coupler are respectively connected with the pumping unit and the data processing unit; signal light generated by the data processing unit and pump light generated by the pump unit are transmitted to the high-nonlinearity medium module through the coupler, the optical nonlinear four-wave mixing effect is excited, idler frequency light is generated, the obtained idler frequency light has the characteristic of spectrum separation, and then all-optical data distribution processing is achieved through filtering of the demultiplexer. According to the method and the system, the satellite network node data processing performance can be greatly improved, satellite resources are saved, and the problems of data parallel and real-time distribution processing of the high-speed backbone laser link at the edge node of the satellite backbone network are effectively solved.

A device useful as a spectrometer or a sensor, comprising a source of a short electromagnetic pulses at a first wavelength and having a full width at half maximum in a range of 1 femtosecond- 1 nanosecond; a sample holder in which the short pulses interact with the sample in the sample holder so as to form an output signal comprising a background residual of the short pulses and a sample response signal in the time domain, and an amplifier comprising nonlinear medium. The nonlinear medium comprises an input for receiving the output signal and a pump pulse at a second wavelength, and a second-order nonlinearity configured for a nonlinear process selectively amplifying the sample response signal, for example by temporally overlapping the pump pulse and the sample response signal.

The invention relates to the technical field of laser pulse compression, and discloses a nonlinear pulse compression method based on multiple through cavities of an annular tire tread and a related device. Comprising the steps that an annular tire tread multi-way cavity is used as a core device of nonlinear pulse compression, the multi-way cavity adopts a closed annular light path, and a tire tread is machined on the cavity surface, corresponding to an annular cavity, of the annular tire tread multi-way cavity so as to carry out astigmatism correction; a low-chirp or negative-chirp dielectric film or a metal film is plated on the cavity surface of the annular cavity, so that positive chirp or nonlinear chirp is prevented from being introduced during pulse reflection; a solid medium or inert gas is inserted into the annular cavity to serve as a nonlinear medium, so that the nonlinear effect in the multi-way cavity is regulated and controlled; a to-be-compressed pulse is incident into an annular tire tread multi-way cavity, and the reflection frequency of the to-be-compressed pulse in the cavity is changed by adjusting an incident angle, so that the optical path of a nonlinear effect and the nonlinear effect intensity are adjusted; and carrying out dispersion compensation on the pulse which is subjected to nonlinear spectrum broadening through the annular tire tread multi-way cavity, so as to realize pulse compression.

This utility model relates to a nonlinear compression device based on an ultrashort femtosecond pulse generated by a perforated cavity mirror, belonging to the field of nonlinear compression devices. The device includes: a perforated cavity mirror with at least one through-hole at a specific position, diameter, and tilt angle, the through-hole ensuring that the incident direction of the input laser beam matches the self-reproducing mode, and the output beam is output in reverse through the same through-hole; a concave reflector coaxial with the perforated cavity mirror; and a nonlinear medium filling the space between the perforated cavity mirror and the concave reflector. The perforated cavity mirror, concave reflector, and nonlinear medium combine to form a multi-cavity laser cavity, where the laser beam undergoes multiple reflections between the perforated cavity mirror and the concave reflector to form a self-reproducing mode. This nonlinear compression device based on an ultrashort femtosecond pulse generated by a perforated cavity mirror effectively solves the problems of damage risk, space occupation, and adjustment difficulty existing in the prior art by introducing a perforated cavity mirror to replace the traditional reflector injection structure.

The present invention discloses a photonic memristor and a preparation method thereof, belonging to the field of semiconductors. The photonic memristor of the present invention is composed of a substrate and a Fabry-Perot resonator. The Fabry-Perot resonator is formed by combining a first reflective film, a graphene oxide nonlinear dielectric layer, and a second reflective film, which can realize the optical spatial parallel propagation and interconnection in optical switching, so as to better perform high-density information storage, improve the processing speed, have low energy consumption, and compared with the existing memristors, have a smaller size, are convenient for integration and manufacturing, and can be mass-produced.

The present invention specifically relates to a method and system for generating CEP-stable optical pulses from input optical pulses having an optical carrier frequency f i of the optical carrier frequency f p and a pulse duration T p . A birefringent medium, a non-nonlinear medium, a dispersive optical system, and a parametric device (DFG) are continuously used to achieve this generation.

The present application relates to the field of optical frequency comb technology, and more particularly to a device and method for generating a bandwidth-adjustable, flat optical frequency comb based on selective filtering. The device comprises: a pump light source and a nonlinear medium; a first tunable reflective filter and a second tunable reflective filter. The laser light generated by the pump light source is coupled into the nonlinear medium using the first tunable reflective filter, or is coupled into the nonlinear medium using an evanescent field, and is output through the second tunable reflective filter to generate an optical frequency comb. A control unit is configured to tune the intersection of the reflection passbands of the first tunable reflective filter and the second tunable reflective filter to adjust the optical frequency comb bandwidth to a target optical frequency comb bandwidth. This solves the problems in the related art of the complexity and high cost of implementing a bandwidth-controllable, broadband optical frequency comb and how to achieve a simple and easily adjustable bandwidth-controllable, broadband optical frequency comb light source.

The invention relates to the technical field of laser pulse compression, and discloses a nonlinear pulse compression method based on multiple through cavities of an annular tire tread. Comprising the steps that an annular tire tread multi-way cavity is used as a core device of nonlinear pulse compression, the multi-way cavity adopts a closed annular light path, and a tire tread is machined on the cavity surface, corresponding to an annular cavity, of the annular tire tread multi-way cavity so as to carry out astigmatism correction; a low-chirp or negative-chirp dielectric film or a metal film is plated on the cavity surface of the annular cavity, so that positive chirp or nonlinear chirp is prevented from being introduced during pulse reflection; a solid medium or inert gas is inserted into the annular cavity to serve as a nonlinear medium, so that the nonlinear effect in the multi-way cavity is regulated and controlled; a to-be-compressed pulse is incident into an annular tire tread multi-way cavity, and the reflection frequency of the to-be-compressed pulse in the cavity is changed by adjusting an incident angle, so that the optical path of a nonlinear effect and the nonlinear effect intensity are adjusted; and carrying out dispersion compensation on the pulse which is subjected to nonlinear spectrum broadening through the annular tire tread multi-way cavity, so as to realize pulse compression.

The present invention discloses a phase-correlated narrow-linewidth multi-wavelength single-frequency fiber laser based on four-wave mixing. The phase-correlated narrow-linewidth multi-wavelength single-frequency fiber laser is composed of a dual-wavelength single-frequency fiber laser seed source, a laser power amplifier, a nonlinear medium, and a filtering device. The dual-wavelength single-frequency fiber laser seed source is used to generate a dual-wavelength laser with high phase correlation; the laser power amplifier is used to amplify the power of the laser; the nonlinear medium is used to stimulate the four-wave mixing effect, thereby generating a multi-wavelength single-frequency fiber laser; and the filtering device is used to filter out a single wavelength of the multi-wavelength laser, the linewidth of which is measured and analyzed by a linewidth test system. The present invention has the characteristics of an all-fiber structure, a simple device, and strong resistance to environmental interference.

The invention discloses a free space Kerr optical frequency comb and a generation method thereof, and relates to the technical field of optical frequency combs. The optical frequency comb comprises a pumping source, an optical isolator, a sampling lens, a focusing lens, a first concave reflecting mirror, a nonlinear medium, a second concave reflecting mirror, a piezoelectric ceramic displacement platform and a frequency locking controller. Pump light emitted by a pumping source sequentially passes through an optical isolator, a sampling lens and a focusing lens and then enters an oscillator composed of a first concave reflector, a nonlinear medium and a second concave reflector. The second concave reflecting mirror is placed on the piezoelectric ceramic displacement platform; the backward reflection Stokes light generated by the oscillator is reflected by the sampling lens and then enters the frequency locking controller, and the frequency locking controller feeds back a signal to the piezoelectric ceramic displacement platform after monitoring the polarization state change of the incident light; and the piezoelectric ceramic displacement platform translates according to the feedback signal, so that the cavity length of the oscillator is changed, and Stokes light frequency stabilization is realized. The invention has the advantages of large output energy, single mode family and the like.

The present application relates to the technical field of laser pulse compression, and discloses a nonlinear pulse compression method and related device based on an annular tire surface multi-pass cavity. The method comprises: using an annular tire surface multi-pass cavity as the core component of nonlinear pulse compression, the multi-pass cavity adopts a closed annular optical path, and the cavity surface of the annular tire surface multi-pass cavity corresponding to the annular cavity is processed with a tire surface for astigmatism correction; coating the cavity surface of the annular cavity with a low chirp or negative chirp dielectric film or metal film to avoid the introduction of positive chirp or nonlinear chirp during pulse reflection; inserting a solid medium or an inert gas into the annular cavity as a nonlinear medium to regulate the nonlinear effect in the multi-pass cavity; incidenting the pulse to be compressed into the annular tire surface multi-pass cavity, and changing the number of reflections of the pulse to be compressed in the cavity by adjusting the incident angle to adjust the optical path and intensity of the nonlinear effect; and performing dispersion compensation on the pulse that has completed nonlinear spectral broadening through the annular tire surface multi-pass cavity to achieve pulse compression.

This invention discloses a continuous terahertz wave radiation source based on optical parametric oscillation in a waveguide cavity, its usage method, and its fabrication method, belonging to the field of optical communication technology. The continuous terahertz parametric oscillation radiation source includes a nonlinear dielectric waveguide layer and a substrate waveguide layer disposed on the upper and lower surfaces of the nonlinear dielectric waveguide layer. Reflective films are disposed on two opposite sides of the nonlinear dielectric waveguide layer to form a waveguide cavity within the nonlinear dielectric waveguide layer. The thickness and width of the nonlinear dielectric waveguide layer both satisfy the wave vector matching condition, and the thickness of the nonlinear dielectric waveguide layer is 5~50 μm. By obtaining a large nonlinear coupling coefficient, a small terahertz propagation loss, and achieving wave vector matching, the continuous terahertz wave radiation source provided by this invention can achieve high terahertz conversion efficiency, the waveguide cavity has a high quality factor, enhances the effective field strength within the nonlinear dielectric waveguide layer, and significantly reduces the terahertz parametric oscillation threshold.

A method of creating a local oscillator light beam LO for a phase-resolved spectroscopy measurement comprises the steps of providing a first measuring light beam (1) and a second measuring light beam (2) being aligned to each other, creating the local oscillator light beam LO by an optical non-linear interaction of a first portion (1A) of the first measuring light beam (1) and a first portion (2A) of the second measuring light beam (2) in an optical nonlinear medium (20), and superimposing the local oscillator light beam LO, a second portion (1B) of the first measuring light beam (1) and a second portion (2B) of the second measuring light beam (2) with a predetermined mutual phase relationship, for providing a sample light beam (3) for the phase-resolved spectroscopy measurement. The local oscillator light beam LO and the second portions (1B, 2B) of the first and second measuring light beams (1, 2) are superimposed with a displaced Sagnac interferometer (10).

The present disclosure provides an optical transceiver chip for an interferometric fiber-optic gyroscope and an interferometric fiber-optic gyroscope. The optical transceiver chip comprises: an on-chip micro-ring resonator comprising a nonlinear medium and configured to be able to couple to a pump light source and receive a pump light signal from the pump light source, and based on a third-order nonlinear effect of the nonlinear medium, generate a non-coherent wide-spectrum optical frequency comb signal from the pump light signal; a fiber coupling device configured to be coupled to the on-chip micro-ring resonator and receive the non-coherent wide-spectrum optical frequency comb signal, the fiber coupling device is further configured to be able to couple to a sensing fiber of the interferometric fiber-optic gyroscope, and provide the non-coherent wide-spectrum optical frequency comb signal to the sensing fiber of the interferometric fiber-optic gyroscope and receive a return light signal from the sensing fiber; and a photoelectric detection device configured to be coupled to the fiber coupling device, receive the return light signal and detect an interference light signal based on interference between the return light signals.

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.

An all-optical signal processor includes one or more input ports configured to receive one or more optical signal channels, a first nonlinear optical processor configured to receive an input signal from the input port and having one or more sections of a first nonlinear medium, an optical phase conjugator optically configured to receive the output signal of the first nonlinear optical processor, a second nonlinear optical processor configured to receive an output signal from the optical phase conjugator and having one or more sections of a second nonlinear medium, and one or more output ports configured to receive the output signal from the second nonlinear optical processor. Variations of the all-optical signal processor can include a single nonlinear optical processor through which an output of the optical phase conjugator co-propagates or counter-propagates with the input signal.

The present invention is notably directed to methods and systems for generating a CEP-stable optical pulse of optical carrier frequency fi from input optical pulses, the input optical pulses having an optical carrier frequency fp and pulse duration Tp. A birefringent medium, a non nonlinear medium, a dispersive optical system, a parametric device (DFG) are successively used to achieve the generation.

A method and apparatus for generating broadband radiation. The method includes directing pulsed pump radiation through a moving non-linear medium, thereby generating broadband radiation from the pulsed pump radiation located within the moving non-linear medium by spectral broadening. The power of the pump radiation located within the moving non-linear medium is at least the critical power for inducing filamentation within the moving non-linear medium.

The invention provides a space-time soliton order regulation and control method based on a panda type polarization-maintaining photonic crystal fiber resonator, and belongs to the field of photonic crystal fibers and fiber resonators, and the method comprises the steps: introducing two symmetrical boron-doped stress regions into a fiber microstructure cladding, and changing the wire drawing temperature to synchronously regulate and control dispersion and birefringence. The anisotropic torsion panda-shaped polarization-maintaining photonic crystal fiber is prepared by adjusting the wavelength and the torsion period at the same time and used for generating an OAM mode. The panda-type polarization-maintaining photonic crystal fiber is adopted as a nonlinear medium, pure high even order dispersion soliton pulse output and a corresponding broadband optical frequency comb are obtained through polarization control over a pumping source, and output space-time soliton order regulation and control are achieved.