50 results about "Nonlinear photonic crystal" patented technology

A bistable photonic crystal configuration comprises a waveguide sided coupled to a single-mode cavity. This configuration can generate extremely high contrast between the bistable states in its transmission with low input power. All-optical switching action is also achieved in a nonlinear photonic crystal cross-waveguide geometry, in which the transmission of a signal can be reversibly switched on and off by a control input, or irreversibly switched, depending on the input power level.

The invention belongs to the field of optical test equipment and a use method thereof and particularly discloses an optical fiber dispersion measurement system which comprises a light source system and an interference measurement system, wherein the light source system comprises a pulse laser, an optical isolator, a narrow band filter slice, a reflector set and a photonic crystal optical fiber for a light source; the pulse laser, the optical isolator, the narrow band filter slice, the reflector set and the photonic crystal optical fiber for the light source are sequentially arranged along an optical path; the interference measurement system comprises a beam splitter, a measurement arm for receiving beams reflected and transmitted by the beam splitter, and a reference arm, and optical fiber assemblies to be measured are arranged in the measurement arm; both ends of the photonic crystal optical fiber for the light source are connected with a three-dimensional optical fiber coupling platform; and the beam splitter is additionally provided with an output end, the optical path arranged behind the output end is sequentially provided with a polarizer, a narrow band filter, an endless single mode photonic crystal optical fiber assembly and a data collection and treatment system. By selecting a highly nonlinear photonic crystal optical fiber with a special ventage structure as the photonic crystal optical fiber for the light source, the system can generate super-continuum spectrum white lights so as to measure a dispersion coefficient with high accuracy, high efficiency and low cost.

An apparatus and methods for generating a substantially supercontinuum-free widely-tunable multimilliwatt source of radiation characterized by a narrowband line profile. The apparatus and methods employ nonlinear optical mechanisms in a nonlinear photonic crystal fiber (PCF) by detuning the wavelength of a pump laser to a significant extent relative to the zero-dispersion wavelength (ZDW) of the PCF. Optical phenomena employed for the selective up-conversion in the PCF include, but are not limited to, four-wave mixing and Cherenkov radiation. Tunability is achieved by varying pump wavelength and power and by substituting different types of PCFs characterized by specified dispersion properties.

A visible light strengthened super continuous spectrum laser system with an all-optical-fiber structure comprises an optical fiber mode-locked laser, a single mode fiber amplifier, an opto-isolator, a double cladding fiber amplifier, a nonlinear photonic crystal fiber. The single mode fiber amplifier is connected with the output of the optical fiber mode-locked laser through an optical fiber; the opto-isolator is connected with the output of the single mode fiber amplifier through the optical fiber; the double cladding fiber amplifier is connected with the output of the opto-isolator through the optical fiber; and an output end of the double cladding fiber amplifier is connected with an input end of the nonlinear photonic crystal fiber through a pulling optical fiber. The system of the invention solves the technical problems that the high-power laser coupling device of the background art has huge volume, low coupling efficiency and limited spectral region. The system has the advantages of simple structure, small volume, high coupling efficiency, reliable engineering, capability of covering the visible light wave band and the like.

A photonic crystal all-optical switch is an all-optical switch (photonic crystal structure), in particular a migrating nonlinear photonic crystal all-optical switch of a defect mode. The photonic crystal all-optical switch comprises triangular lattice photonic crystals (1), a waveguide area (2), a traction area (3) and a nonlinear resonant cavity (4), wherein the triangular lattice photonic crystals (1) are large air hole type photonic crystals in triangular periodic distribution along X and Z axes, symmetric linear defects are introduced at two ends of the triangular lattice photonic crystals to form the waveguide area (2), a central air hole of the triangular lattice photonic crystals (1) is provided with the nonlinear resonant cavity (4), the traction area (3) is arranged between the waveguide area (2) and the nonlinear resonant cavity (4), and signal light is input from the left end of the waveguide area (2) and output from the right end of the waveguide area (2); and control light vertical to the X and Z axes is incident to the central nonlinear resonant cavity (4) along a medium column.

A laser system (10) for use in photonic excitation investigation of a target object, in which the target object interacts with incident photons and emits a corresponding photon which is detected and used to generate an image of the target object. The laser system (10) includes a pulsed fiber laser (14) for producing a laser beam, and a non-linear photonic crystal fiber (16) for carrying the laser beam from the laser (14) to an instrument (18) for photonically exciting the target object. The photonic crystal fiber (16) allows for switching, or tuning, the wavelength of the laser beam. In two-photon microscopy, the laser system (10) allows for providing multiple wavelengths for exciting a plurality of different fluorophores simultaneously. In coherent Raman imaging and spectroscopy, the laser system (110) allows for using a single laser to provide two laser beams of different wavelengths.

The present invention relates to a method to control the nucleation and transverse motion of 180° inverted domains in ferroelectric nonlinear crystals. It includes a process composing of a high temperature oxidation of the first metal layer and a pulsed field poling of the second electrodes. The main object of present invention is to provide domain inversion of ferroelectric nonlinear crystals with field control the nucleation and transverse motion of inverted domains and two-dimension nonlinear photonic crystals for time-domain multiple-wave simultaneous lasers and space filter function. Another object of present invention is to provide space-charge effect for screened edge field beneath the metal electrode, The other object of present invention is to provide the constraint of inverted domain nucleation in the oxidized electrode for arbitrarily geometrical form of 2D ferroelectric lattice structure.

The invention relates to an ultrashort laser pulse time domain compression device and method. The device comprises a femtosecond laser oscillator, a Faraday isolator, a first objective lens, a high nonlinear photonic crystal fiber, a second objective lens and a 4f pulse shaping unit. Femtosecond pulses emitted by the femtosecond laser oscillator pass through the Faraday isolator and then are coupled into the high nonlinear photonic crystal fiber through the first objective lens to generate continuous spectral pulses. The continuous spectral pulses are collimated by the second objective lens and then enter the 4f pulse shaping unit. The 4f pulse shaping unit is configured to measure and compensate the frequency-domain phase distortion of the continuous spectral pulses, and compress the continuous spectral pulses. The frequency-domain phase distortion is determined by phase interference scanning in the multi-photon pulses. The ultrashort laser pulse time domain compression device and method greatly improve the precision of the pulse time-domain compression by using the frequency-domain 4f pulse shaping unit.

The invention discloses a small-core cluster photonic crystal fiber with a large effective mode field area and high non-linearity, which pertains to the technical field of fibers. The effective mode field area of the photonic crystal fiber is composed of the bunching of a plurality of fibers with a core diameter of 1 to 2 microns; small air vent holes are arranged around each small fiber core to form a covering; the periphery of a small bunching core is the structure of a multi-layer air vent hole covering. The photonic crystal fiber has the advantages that the photonic crystal fiber retains and promotes the original feature of high non-linearity, has relatively large effective mode field area and can bear relatively large pump energy; when the photonic crystal fiber is combined with a photonic crystal fiber mode lock laser with high power, a small-sized super-continuum laser source with high power is formed.

The invention relates to an all-optical buffer based on a photonic crystal fiber and pertains to the all-optical buffer devices in an optical network, which solves the problems that the existing optical buffers have high pump power and optical circuits are easy to be damaged. The invention comprises a data caching optical circuit which is composed of a highly-nonlinear photonic crystal fiber, etc., and a read and write control optical circuit. The invention is provided with a Mach-Zehnder switch at an input terminal and a Mach-Zehnder switch at an output terminal between which the data caching optical circuit and a direct data channel composed of the optical fiber pass through in parallel; the Mach-Zehnder switch at an input terminal and the Mach-Zehnder switch at an output terminal are controlled by a buffer on-off controller so as to select optical signals to pass through the direct data channel or the data caching optical circuit. The all-optical buffer of the invention can realize the continuous and controllable cache time of the optical signal under rather low pump optical power and has simple structure, low cost, a short signal storage medium, low energy consumption of the system as well as continuous and adjustable cache time, and has universality to the photonic crystal fiber of a small mode field.

The invention discloses a photon crystal optical fiber, whose transect includes a fiber core and a cladding. The cladding is identical to the common photon crystal optical fiber, and is a peripheral area surrounding the fiber core and homogeneously distributed with identical structural airports. The airports are periodically arranged in the optical fiber base material, the dimension of the airports is the wavelength magnitude, every three adjacent airport units constitute a regular triangle. The fiber core is jointly constituted by an optical fiber base material locating at the center part of the optical fiber end-face and another solid material, wherein, the refractivity of the solid material is higher than that of the optical fiber base material, two blocks of solid material are symmetric distributed at the both sides of the optical fiber end-face center and the minimum distance of their outer margins should be smaller than 400nm in order to produce a narrow slit. The transect of the solid high-index material may be circular, elliptical shape, square or oblong; the diameter of the circular cross section, the minor axis diameter of the elliptical cross-section, the edge length of the square cross section, and the short edge length of the oblong cross section should be smaller than 400nm. By changing the fiber core structure of the photon crystal optical fiber, the invention uses the narrow slit to limit the light to spread in the nano-scale dimension low refractivity base material, thereby largely decreasing the effective model field area, and causing the photon crystal optical fiber to have ultra-high non-linearity and ultra-low limitation waste. The invention uses a simple and convenient manufacturing structure to resolve the problem in the prior photon crystal optical fiber technique, which is be difficult to implement ultra-high non-linear.

The invention is suitable for the field of optical fiber and provides a device for generating super continuous spectrums. The device comprises a continuous wave fiber laser, a high nonlinear photonic crystal fiber and a high nonlinear normal dispersive optical fiber, wherein the continuous wave fiber laser is used for providing pump light; the high nonlinear photonic crystal fiber is welded with an output tail fiber of the continuous wave fiber laser and is used for performing nonlinear conversion on the pump light provided by the continuous wave fiber laser so as to form the continuous spectrums; the high nonlinear normal dispersive optical fiber is welded with the high nonlinear photon crystal fiber and is used for flattening and expanding the formed super continuous spectrums. The device for generating the super continuous spectrums can flatten the super continuous spectrums with high spectral intensity peaks. Simultaneously, the spectrums further expand towards a long wave direction so as to obtain high flat broadband super continuum output.

The invention provides a multi-wavelength micro illumination device. In the device, a laser pulse output by a picosecond pulse laser or a femtosecond pulse laser is incident to a nonlinear photonic crystal fiber to obtain a broadband laser source; the pulsed laser beam output by the broadband laser source is incident to an acoustooptical modulator to obtain a laser pulse beam with a repetition frequency; a beam splitter and a plurality of reflectors are arranged on the optical path of the laser pulse beam; the laser pulse beam is divided into n parallel output beams (n is a natural number equal to or larger than 2); a dispersion prism or a diffraction grating, a lens (a), a spatial light modulator and a lens (b) are sequentially arranged on the optical path of each output beam; and (n-1) output beams respectively pass through a right angle prism after passing through the dispersion prism or the diffraction grating, the lens (a), the spatial light modulator and the lens (b) to obtain n parallel output beams with different delay time. The multi-wavelength micro illumination device provided by the invention can provide laser wavelengths with a wide waveband range from near ultraviolet to mid-infrared and high spectral energy density above 1 nJ / nm, and is suitable for excitation of the most of fluorescence and Raman samples. Additionally, the plurality of laser wavelengths are from the same laser source so as to obviate the problem of synchronous time maladjustment, and the apparatus cost can be reduced greatly by using one pulse laser.

The invention provides an active amplification type optical parameter oscillation feedback system. The active amplification type optical parameter oscillation feedback system comprises: a pumping source, an optical coupling device, a non-linear photonic crystal optical fiber, a light splitting device, an active amplifier and an optical delaying device, wherein the pumping source is used for generating and outputting laser; the optical coupling device is used for coupling laser output by the pumping source and laser transmitted by the optical delaying device; the coupled laser is transmitted to the non-linear photonic crystal optical fiber and then is processed; the processed laser is transmitted to the light splitting device to be split into two paths of light beams, wherein one path of light beam is directly output and the other path of light beam is transmitted to the active amplifier; the active amplifier is used for widening gains of a laser light spectrum, and improving the optical power of the laser; the laser is transmitted to the optical delaying device for delaying and the delayed laser is transmitted to the optical coupling device again. According to the active amplification type optical parameter oscillation feedback system, optical parameter oscillation feedback of the laser is realized, the optical power of the laser of a feedback loop can be improved and the gains of the light spectrum are widened, so that the conversion efficiency of the optical parameter oscillation feedback is improved.

The invention provides a high birefringence large non-linear photonic crystal fiber. The high birefringence large non-linear photonic crystal fiber having a hexagonal crystal lattice oval air hole array structure composed of first oval air holes and second oval air holes and working in an intermediate infrared range from 3 [mu]m to 5 [mu]m includes a fiber core and a cladding disposed on an optical fiber background material. The cladding has six-layer hexagonal crystal lattice oval air hole arrays composed of first oval air holes and second oval air holes having identical long axis and different short axes. The second oval air holes are distributed along the y axis while the first oval air holes are distributed along the x axis. The fiber core is arranged in the solid area of the center position of the optical fiber background material. High birefringence of the optical fiber as high as 0.1177 is acquired in a wavelength range from 3 [mu]m to 5 [mu]m and the corresponding beat-length is 42.4 [mu]m. The nonlinear coefficient of the optical fiber in the x polarization direction and the y polarization direction is 38390w-1km-1 and 49760w-1km-1.

The embodiment of the invention provides an infrared single photon detection apparatus comprising a nonlinear photonic crystal waveguide, a filter, and a visible light single photon counting module, wherein the nonlinear photonic crystal waveguide and the filter are integrated into a single chip; the nonlinear photonic crystal waveguide is used to up-convert an infrared single photon signal into a visible light single photon signal. The filter is used for filtering the noise in the visible light single photon signal. The visible single photon counting module is used for detecting the visible light single photons of the filtered visible light single photon signal. The low practicability in the prior art can be solved by carrying out infrared single photon detection by means of the infrared single photon detection apparatus having a smaller volume.

The invention discloses a high power frequency converter of small core diameter beaming high non-linear photonic crystal fiber, which belongs to a high power ultra continual Laser Technology in the laser field. The converter is composed of a single high power pulse laser, a non-spherical surface collimation beam expander or micro-lens array, the small core diameter beaming high non-linear photonic crystal fiber, a non-spherical surface focusing lens or micro-lens array and big model field photonic crystal fiber. Or the converter is composed of the single high power pulse laser, the non-spherical surface collimation beam expander or micro-lens array, the small core diameter beaming high non-linear photonic crystal fiber and the big model field photonic crystal fiber. The converter of the invention has the advantages of having the ultra continual laser output capacity of above dozens of watt.

The invention relates to a hybrid multiplexing passive optical network and a communication method thereof, which are characterized in that a pumping wave which can be used for four-wave mixing frequency is injected into an optical communication line; after carrying out wavelength division multiplexing (FWM), the pumping wave and a user terminal uplink optical signal are injected into a high non-linear optical fiber or a high non-linear photonic crystal optical fiber; the high non-linear optical fiber or the high non-linear photonic crystal optical fiber realizes the FWM between the pumping wave and the user terminal uplink optical signal and generates a wavelength conversion optical signal; and after passing through a wavelength division multiplexer, the wavelength conversion optical signal is transmitted to an optical line terminal, thereby realizing optical signal uplink communication and supporting the transmission of a plurality of time division multiplexing optical networks in a single optical fiber. The hybrid multiplexing passive optical communication network utilizes the FWM effect in the high non-linear optical fiber and the high non-linear photonic crystal optical fiber, has favorable compatibility with original ONU equipment and the passive characteristics of ODN, can realize the upgrading of the network without changing the ONU equipment and greatly reduce the reforming cost of the network.

The invention discloses a micro-nano imaging detection experiment device based on photoacoustic beam shaping. The micro-nano imaging detection experiment device comprises a dye laser light source, a light beam shaping forward scanning probe based on nonlinear photonic crystals, a first reflecting mirror, a three-dimensional electric platform, a beam expanding mirror, frosted glass, coupling liquid, an ascending and descending table, a sample pool, an energy converter, an embedded wavefront control backward tracking probe, a lock phase amplifier, a data collector and a computer. The experimentdevice can effectively work in a complicated photoacoustic field regulation control and self-adaption wavefront control marking-free detection mode; the computer is respectively connected with the dyelaser light source, the light beam shaping forward scanning probe, the three-dimensional electric platform, the energy converter, the light beam shaping forward scanning probe and the lock phase amplifier through signal wires. The multi-signal extension compensation correction, fast shearing, precise registering and the like are realized; The qualitative, positioning and quantitative EA (extension analysis) on multi-mode relevant target points of occurrence, development, transfer and induction apoptosis can also be realized.

The present invention relates to a nonlinear fiber, in particular to a photonic crystal fiber with high nonlinearity and flattened dispersion at long wavelength, and pertains to the field of fiber communication and optical signal processing. The structure of the present invention is characterized in that a low duty-cycle hole defect structure is provided in the pure-quartz fiber core zone, and the fiber cladding comprises a high duty-cycle hole periodic structure. The nonlinear photonic crystal fiber in the present invention, compared with the simple total-reflection nonlinear photonic crystal fiber, overcomes the bottleneck that zero dispersion can only be adjusted at short wavelength, and realizes that zero dispersion can be adjustable in a wide range of spectrum and the property of flattened dispersion is provided at long wavelength. The invention can be widely applied to optical devices in the field of communication-wavelength photonic technology, such as the multi-wavelength light source for long wavelength communication, the quantum information source and so on.

The invention provides a method for preparing high non-linearity photon crystal fiber, comprising that (1), synthesizing high non-linearity glass that from photon crystal fiber angle, using general method to synthesize the oxide glass and non-oxide glass with high non-linearity, (2), preparing high non-linearity photon crystal fiber preformed rod that using the synthesized high non-linearity glass as base material to prepare a photon fiber model with single core structure, correcting the rough part in the mode, based on the effects of independent parameter on the change tendency of effective area, crystallization ability in different temperatures and thermal stress in different cooling speeds, finding the technique and preparing the preformed rod, (3), preparing high non-linearity photon crystal fiber that drawing the preformed rod, to prepare the fiber. The inventive photon crystal fiber has high non-linearity.

The invention discloses a photonic crystal fiber soliton output wavelength stabilizing device. The system comprises a stable wavelength detection device, a high resolution data acquisition card (10) and a computer feedback control system (11), wherein the stable wavelength detection device is composed of a femtosecond laser (1), an electronic-control liquid crystal wave plate (2), a polarizer (3),an optical fiber coupling mirror (4), a highly nonlinear photonic crystal fiber (5), an optical fiber collimation beam expander (6), a 95:5 beam splitter (7), a narrowband filter (8) and a photoelectric detector (9). Compared with the prior art, the photonic crystal fiber soliton output wavelength stabilizing device and method disclosed by the invention have the advantages of simple device structure and quickness in method adjustment; while a photonic crystal fiber soliton output wavelength adjusting range is kept, the wavelength tuning speed is improved, and output soliton wavelength stability is improved.

The invention provides a nonlinear photonic crystal capable of directly generating two-photon frequency and path super-entanglement. The nonlinear photonic crystal selects a 5% MgO doped LiNbO3 crystal under the conditions of room temperature and class I phase matching (e->-o+o). Meanwhile, the invention provides a two-photon frequency and path super-entanglement generation method based on the nonlinear photonic crystal. According to the method, pump light is normally incident to the surface of the nonlinear photonic crystal in the positive z direction, signal light and idle light are generated after interaction, and the signal light and the idle light meet the frequency and path super-entanglement relation. Simulation is carried out on the nonlinear photonic crystal and the two-photon frequency and path super-entanglement generation method thereof, it is verified that the maximum entanglement state can be generated, other parameter processes are effectively inhibited, and the super-entanglement state with relatively high quality is generated.

The invention discloses a double-frequency CARS measuring device and method based on a bound-state light soliton. The device at least comprises a femtosecond laser (1), an ultra-short pulse beam splitting adjusting part, a Stokes light pulse generating and transmitting light path, a pump light transmitting light path, a beam combiner (15) and a CARS microimaging system (16) which are connected insequence. Based on a soliton self-frequency-shift effect and a birefringence effect when an ultrashort pulse is transmitted in a high-nonlinearity photonic crystal fiber, a bound-state light soliton with overlapped time domains and separated wavelengths are generated. When the bound-state light soliton is used as a Stokes light pulse of a CARS system, the bound-state light soliton can simultaneously act with a pump light pulse to realize simultaneous excitation and detection of resonant frequencies of two molecules to be detected. In the invention, a system structure of the traditional CARS measurement system is simplified, system cost is reduced, and a chemical selective imaging capability and a multi-molecule simultaneous detection capability of the CARS system are improved.

The invention provides a Raman laser enhancement device and method based on a high-nonlinearity photonic crystal fiber, and the structure of the Raman laser enhancement device consists of an ytterbium-doped fiber laser, a Faraday isolator, a fiber combiner, a polarization controller, a single-mode fiber SM1, a single-mode fiber SM2, a high-nonlinearity photonic crystal fiber (HNL-PCF), Bragg gratings FBG1, FBG2, FBG3, and FBG4, a photonic crystal fiber, a T-shaped connector 1, a T-shaped connector 2, a spectrum analyzer and a computer processing system.

A laser system (10) for use in photonic excitation investigation of a target object, in which the target object interacts with incident photons and emits a corresponding photon which is detected and used to generate an image of the target object. The laser system (10) includes a pulsed fiber laser (14) for producing a laser beam, and a non-linear photonic crystal fiber (16) for carrying the laser beam from the laser (14) to an instrument (18) for photonically exciting the target object. The photonic crystal fiber (16) allows for switching, or tuning, the wavelength of the laser beam. In two-photon microscopy, the laser system (10) allows for providing multiple wavelengths for exciting a plurality of different fluorophores simultaneously. In coherent Raman imaging and spectroscopy, the laser system (110) allows for using a single laser to provide two laser beams of different wavelengths.

The invention discloses a high nonlinear photonic crystal fiber which relates to the field of a photonic crystal waveguide structure. A micropore area is internally provided with air pores which are distributed in the axial direction of the fiber and penetrate through the whole fiber. The plurality of air pores are arranged around the axis of the fiber core. At least six layers of annular rings are arranged around the fiber core, namely a first layer of annular ring, a second layer of annular ring, a third layer of annular ring, a fourth layer of annular ring, a fifth layer of annular ring and a sixth layer of annular ring from inside to outside. Furthermore the cross section of each ring of annular ring is of a right hexagon. Each layer of annular ring is obtained through arranging a plurality of air pores. The internal diameter of the air pores of the first layer of annular ring, the second layer of annular ring, the third layer of annular ring, the fourth layer of annular ring, the fifth layer of annular ring and the sixth layer of annular ring are D1, D2, D3, D4, D5 and D6, and furthermore D1<D3=D5<D2=D4=D6. The high nonlinear photonic crystal fiber has a characteristic of certain dispersion flatness, and furthermore has advantages of forming good nonlinear transmission in a certain range and supplying better support for high nonlinear application.

The invention relates to a supercontinuum light source based on a noise-like mode locked pulsed pump. The light source comprises a noise-like mode locked short pulse seed source for providing a stable short pulse; a pulse amplification system for amplifying the pulse power of the stable short pulse; and a highly nonlinear photonic crystal fiber for broadening the spectrum of the pulse after being subjected to pulse power amplification by the pulse amplification system to obtain a flat supercontinuum source covering the ultraviolet to mid-infrared. The light source of the invention is simple in structure, relative low in cost, relatively high in efficiency, and can amplify the light pulse into the flat super-continuum spectrum enough to generate high power just through one-grade amplification.