140 results about "Waveguide grating" patented technology

Gradient encapsulation of waveguide outcoupler gratings for control of diffraction efficiency and directionality includes a first grating formed over a substrate, the first grating having a plurality of first structures extending away from the substrate, the first grating corresponding to an outcoupler. The device includes a first encapsulant disposed in one or more gaps formed between adjacent first structures, where a fill ratio of the first encapsulant decreases along the first grating. Also described herein are methods for fabricating the device.

The invention provides a photon parallel matrix convolution operation chip which can be applied to the technical field of integrated photonics and optical calculation. The chip is integrated by a 1 * N array waveguide grating, a 1 * 2 beam splitter array, an input matrix modulator array, two N * 1 array waveguide gratings, two 1 * N beam splitters, a weight matrix modulator array, an M * M array waveguide grating detector array and a detector array. Main functional devices are integrated in a monolithic mode, the system is compact, the complexity and power consumption of the system can be effectively reduced, and the calculation efficiency is improved.

The invention discloses a polarization insensitive filter based on a sub-wavelength grating structure, and belongs to the technical field of integrated photonic devices. The filter comprises an input transition waveguide, a multimode waveguide grating and an output transition waveguide which are connected in sequence. The multimode waveguide grating is composed of a central sub-wavelength grating waveguide and Bragg gratings symmetrically distributed on the two sides, and the effective refractive indexes of TE polarization and TM polarization are equal by adjusting the waveguide width and duty ratio of the central sub-wavelength grating, so that the polarization sensitivity of the device is eliminated fundamentally. And the input / output transition waveguide adopts a transition mode of mixing a tapered waveguide and a sub-wavelength grating waveguide, so that low-loss mode transmission between a straight waveguide and a multimode grating is realized. According to the invention, the anisotropic equivalent medium characteristic of the sub-wavelength grating is utilized, a function of simultaneously and effectively filtering TE and TM polarization is realized, and the filter has the advantages of polarization insensitivity, flexible design, compact structure, simple process and compatibility with a CMOS (Complementary Metal Oxide Semiconductor) process, and has important application value in the fields of optical communication, optical interconnection and the like.

The invention relates to a waveguide grating, in particular to a method for manufacturing a waveguide grating with continuous gradually-changing groove depth, which comprises the following steps of: accurately measuring and calibrating ion beam current density distribution of a used ion beam in a working plane; establishing a cooperative control model associated with a target groove depth curve, ion beam current density distribution and scanning speed, associating the etching depth with the ion beam total dose, and accurately controlling the ion beam total dose received by each point on the waveguide grating by dynamically regulating and controlling the scanning speed of the substrate relative to the ion beam, so as to realize accurate control of the etching depth. The accurate control on the groove depth distribution is realized; based on the cooperative control model, the scanning speed corresponding to the target groove depth curve is solved by combining the set target groove depth curve and the calibrated ion beam current density distribution; and performing ion beam etching based on the solved scanning speed, and finally forming a continuous gradual change groove depth accurately corresponding to the target groove depth curve on the waveguide grating. The method can effectively overcome the defect that the high-precision waveguide grating with the continuous gradually-changing groove depth is difficult to manufacture.

Distances between photonic integrated circuits and multiport optical probes can be established by emitting an optical beam from a first optical port of the multiport optical probe so that the optical beam is coupled into a first waveguide section of a PIC. This optical beam portion is reflected from a surface of the multiport optical probe back to the PIC. At suitable PIC-probe distances, the optical beam is coupled by a second waveguide grating to propagate in a second waveguide section and is then emitted to a second optical port of the multiport optical probe by a third waveguide grating coupler and directed to a detector. The detector signal is used to determine or adjust PIC-probe separation.

A high-crosstalk array waveguide grating structure capable of changing waveforms and improving demodulation resolution comprises an input optical waveguide, the output end of the input optical waveguide is connected with the input end of a coupling module, and the output end of the coupling module is sequentially connected with a first slab waveguide, an array waveguide and a second slab waveguide. The output end of the second slab waveguide is respectively connected with the input ends of the first output waveguide, the second output waveguide, the third output waveguide and the fourth output waveguide; according to the invention, the array waveguide grating structure connected with the coupling module at the input end is adopted, so that the output spectrum of the adjacent output channels has large bandwidth, the large dynamic range of the adjacent channels during FBG wavelength demodulation is ensured, an optical waveguide width value different from a design value is adopted, the top end waveform of the output spectrum is regulated and controlled, and the demodulation precision is improved. On the premise of ensuring that the dynamic range of adjacent output channels is not changed, the resolution of the demodulation wavelength is improved; the device has the advantages of simple structure, large bandwidth, high crosstalk and high wavelength demodulation resolution.

The invention discloses an oil and gas pipeline sand content test sound wave optical fiber sensor, and particularly relates to the technical field of sensors, which comprises a rare earth doped silicon dioxide optical waveguide sheet, a vibration transduction structure, a phase shift waveguide grating and a phase shift wave. The device further comprises a photoelectric converter, a signal amplifier, a filter, a fragrance clamping filter and a vibration signal detector. The rare earth doped silicon dioxide waveguide sheet is located on the vibration transduction structure, and the phase shift waveguide grating is inscribed in the rare earth doped silicon dioxide waveguide sheet. The micro-vibration optical chip sensor based on the photoacoustic spectrum is simple and firm in structure, easy to manufacture and convenient to integrate with other systems, and the problem of integration of a traditional optical fiber distributed sensing system can be effectively solved.

The invention provides a substrate integrated waveguide slot array antenna based on a waveguide grating filtering structure. A radiation slot array antenna is formed by arranging a radiation slot array on a first metal layer on the surface of a substrate integrated waveguide; secondly, a grating filtering structure is formed by periodically arranging metalized blind hole groups at the bottom of the substrate integrated waveguide. According to the substrate integrated waveguide slot array antenna based on the waveguide grating filtering structure, selection and propagation of a specific working frequency band are realized by controlling the aperture of the metalized blind holes, the hole pitch of the metalized blind hole group, the line pitch, the waveguide shape and the opening mode of the radiation slot array in the substrate integrated waveguide slot array antenna based on the waveguide grating filtering structure; and the manufacturing process of the substrate integrated waveguide slot array antenna based on the waveguide grating filtering structure is simplified while effective integration of the substrate integrated waveguide slot array antenna and the grating filtering structure is realized.

The invention discloses an on-chip waveguide grating antenna phase error detection method comprising the following steps: amplifying a waveguide grating antenna near field, and receiving the amplified near field by using a camera; irradiating the target surface of the camera through obliquely incident plane reference light, interfering with the near field amplified by the waveguide grating antenna to form an interference image, and collecting the interference image; and obtaining a one-dimensional sine interference curve of the interference image of each waveguide grating antenna unit, calculating the period of the one-dimensional sine interference curve and a difference value between peak values of the one-dimensional sine interference curve of the interference image of each waveguide grating antenna unit, and dividing the difference value by the period and multiplying by the wavelength to obtain the size of the phase error between the waveguide grating antenna units. According to the technical scheme, direct measurement of the phase error between the waveguide grating antennas can be achieved, and the defect that in the prior art, an optimization iterative algorithm is adopted to conduct indirect phase error detection and evaluation on the far field of the waveguide grating antennas is overcome.

The invention discloses a waveguide grating for realizing diffraction efficiency gradual change, a preparation method and equipment. And the grating depth and the duty ratio are monotonically increased along the etching direction, so that the spatial gradient distribution of the diffraction efficiency is obtained. The method comprises the following steps of: firstly, forming periodic photoresist stripes on a substrate by utilizing an interference photoetching technology to obtain an initial grating pattern; and then, the substrate is placed in a plasma etching system, and the depth and duty ratio of the grating are monotonically increased along the etching direction by regulating and controlling the etching time or etching rate of different areas, so that the spatial gradient distribution of diffraction efficiency is realized. The waveguide grating disclosed by the invention effectively compensates attenuation of light in a waveguide transmission process, and the uniformity and imaging quality of AR display application and the like are remarkably improved. The problem of uneven brightness caused by light energy transmission attenuation of the waveguide grating in the prior art can be effectively solved, the manufacturing cost is low, the process expandability is high, and the waveguide grating is suitable for various waveguide optical display scenes such as mixed reality (MR) and virtual reality (VR).

The invention discloses a double-reflection grating coupler for spatial optical coupling, which comprises a substrate layer, an oxide lower cladding layer and an optical waveguide layer which are sequentially stacked from bottom to top, a first light reflection structure is arranged between the substrate layer and the oxide lower cladding layer, and a supporting polar plate is arranged above the optical waveguide layer. A second light reflection structure is arranged between the supporting polar plate and the optical waveguide layer; the optical waveguide layer comprises a left optical waveguide, a grating area and a right optical waveguide which are sequentially arranged from one side of the substrate layer to the other opposite side, and space light enters the grating area, is reflected by the first light reflection structure and the second light reflection structure, reflects an uncoupled part back to the grating area for coupling, and is output through the right optical waveguide. According to the invention, the problem of low coupling efficiency in coupling of the spatial light and the optical waveguide in the turbulent channel in the prior art is solved.

A waveguide grating coupler (WGC) for coupling light transmitted between an integrated optical waveguide and an optical fiber and a method for making the waveguide grating coupler are provided. The waveguide grating coupler working for dual polarization includes a grating layer having a first plurality of etched holes and an overlay layer disposed on the grating layer, having a second plurality of etched holes. At least one of the second plurality of etched holes partially overlaps a corresponding etched hole of the first plurality of etched holes. The overlay layer is configured to create a shift of every period of grating to the grating layer to achieve upwards constructive interference and downwards destructive interference of light such that coupling efficiencies of both vertical grating coupling and angle coupled grating coupling are enhanced for a single mode optical fiber, a few mode optical fiber, or a multi-mode optical fiber.

The invention relates to a 3 [mu] m SOI-based polarization insensitive waveguide grating antenna for optical sensing. The waveguide grating antenna provides a substrate and a ridge waveguide located above the substrate; grating teeth are formed on the upper surface of the ridge waveguide through shallow etching; slab areas on the two sides of the ridge waveguide are provided with deep etching which is etched to the buried oxide layer. The OPA transmit-receive system introduced in the invention has high diffraction efficiency (gt; 70%), which is far greater than 50% emission efficiency of a conventional fishbone-shaped antenna; polarization is insensitive, and inherent loss of a polarization controller in the system can be eliminated; and the beam divergence is small (less than 0.01 degree), and the method has a good application prospect.

The invention discloses a calculation spectrometer based on a random multimode waveguide grating and a spectrum reconstruction method. Comprising a silicon substrate layer, a silicon dioxide buried oxide layer, a lithium niobate waveguide layer, a silicon dioxide coating layer and an interdigital electrode which are sequentially stacked from bottom to top, a mode multiplexer, a multi-mode waveguide spiral line and multi-mode waveguide gratings are formed on the lithium niobate waveguide layer, the mode multiplexer is communicated with the multi-mode waveguide spiral line, the multi-mode waveguide spiral line at least comprises a section of multi-mode straight waveguide, a plurality of non-periodically distributed multi-mode waveguide gratings are arranged on the multi-mode straight waveguide, and the multi-mode waveguide gratings are arranged on the multi-mode straight waveguide. And each multimode waveguide grating unit adopts a Bragg grating structure and comprises two groups of grating tooth structures which are respectively positioned on two sides of the multimode straight waveguide. According to the invention, the electrical control logic can be simplified, the disordered resonance of different modes in the spiral line can provide high spectral reconstruction resolution, and meanwhile, the lithium niobate electro-optical modulation can realize rapid and low-power consumption measurement channel scanning.

The invention provides signal coding equipment, an imaging system and an imaging method. The signal coding equipment comprises an array waveguide grating, a coding optical fiber, a delay optical fiber and an optical splitter, the array waveguide grating is configured to convert an initial signal emitted by the light source into multiple paths of target signals; the optical splitter is configured to combine multiple paths of target signals and then emit the combined signals; a plurality of paths of coding optical fibers and a plurality of paths of delay optical fibers with different lengths are arranged behind the array waveguide grating, and each path of delay optical fiber is connected to the coding optical fiber of the corresponding coding sequence; the delay optical fiber is configured to delay a transmitted target signal, and the coding optical fiber is configured to perform pulse coding on the transmitted target signal. According to the invention, the original pulse signal is coded by using the sequence code with good orthogonality, so that the signal processing accuracy is improved. And the delay optical fibers are grouped, so that the corresponding channels in each group of channels can be simultaneously transmitted, the signal transmitting time is shortened, the signal processing efficiency is improved, and the point acquisition rate can be improved while the fuzzy distance is expanded.

A long-period waveguide grating type sensor comprises a glass substrate, a waveguide core layer extending linearly is arranged in the glass substrate, and a wrapping layer is arranged on the periphery of the waveguide core layer. The waveguide core layer is sequentially composed of a first cylindrical core layer, a long-period grating core layer and a second cylindrical core layer from front to back, and the radius of the long-period grating core layer changes in a sine period mode from front to back. The first cylindrical core layer is an optical signal input end, and the second cylindrical core layer is an optical signal output end. The high-sensitivity rapid measurement of the gas is realized by utilizing the high-sensitivity response of the characteristic absorption peak wavelength of the transmission spectrum trough to the refractive index disturbance of the external environment, and meanwhile, the manufacturing method is simple and the cost is low.

The invention discloses a distributed feedback laser array line width narrowing device and method based on self-injection feedback, and the device is characterized in that a laser array is connected with an array waveguide grating, the array waveguide grating is connected with an optical fiber circulator, and the optical fiber circulator is connected with an optical fiber coupler; the output of the laser array is combined through the array waveguide grating and then input into the optical fiber circulator, part of laser entering the optical fiber coupler from the optical fiber circulator passes through the optical fiber circulator and the array waveguide grating again and is injected into the laser array in the form of optical feedback, and the working state of the laser array is influenced by the optical feedback. And the line width of the laser array is narrowed. Through the synergistic effect of the laser array, the array waveguide grating, the optical fiber circulator and the optical fiber coupler, a self-injection feedback loop is constructed, part of output laser is re-injected into the laser unit after wave combination and light splitting, and phase noise is suppressed through optical feedback, so that the linewidth is remarkably reduced.

The present application relates to the technical field of photolithography process, and more particularly to a kind of periodical scanning half-period optical waveguide grating preparation method, adopts multi-dimensional defect feature extraction and dynamic compensation algorithm, combined with the space-time synchronous modulation technology of light intensity distribution, significantly improves the defect masking efficiency;Through the multi-parameter collaborative optimization strategy under the closed-loop control architecture, the self-adaptive evolution mechanism of process parameters is formed, and the performance stability of grating structure under complex working conditions is guaranteed.The technical scheme innovates the whole process from light field modeling, motion control to defect repair, solves the common technical problems of grating period distortion and defect residue in the existing process, and provides a mass production solution for high-reliability grating devices for dense wavelength division multiplexing systems.

The invention discloses a topology protection Hong-Ou-Mandel interferometer based on a pi phase regulation and control grating, and belongs to the technical field of integrated photonics and quantum optics. The interferometer comprises a first waveguide and a second waveguide which are arranged side by side on a silicon dioxide substrate, and each waveguide comprises an input waveguide, a grating waveguide and an output waveguide. The two grating waveguides are provided with periodic notch grooves, and the positions of the notch grooves are symmetrically distributed about a waveguide center connecting line, so that a pi coupling phase difference is introduced between coupling in the two waveguides. The TE-TM coupling strength in the waveguides is enabled to be equal to the TE-TE coupling strength and the TM-TM coupling strength between the waveguides by adjusting the waveguide distance and the notch groove size, and the system enters a topological non-trivialness phase when delta phi is equal to pi, so that a compact topological boundary mode is formed. The structure provides an evolution path protected by topology for two-photon HOM interference, realizes interference visibility close to a theoretical limit, shows strong robustness for manufacturing errors and propagation distance changes, is obviously reduced in device size, and is suitable for high-density integrated quantum photon chips.

According to the exposure method of the multi-region distributed waveguide grating, the waveguide grating comprises a waveguide substrate, and is characterized in that a first grating, a second grating and a third grating which are independent and adjacent are arranged on the waveguide substrate, and the first grating, the second grating and the third grating are located in different regions of the waveguide substrate. Gratings with different periods and stripe directions are processed in a short-wave coherent laser double-beam holographic interference exposure mode, and a multi-area distributed waveguide grating is formed. Compared with the prior art, the exposure difficulty of the waveguide grating can be reduced, the assembling and debugging simplicity of a light path is improved, the processing efficiency is improved, the processing cost is reduced, and engineering production is easier.

an optical intensity modulation device (100) comprising: an optical modulator (102) operative to modulate a continuous wave optical carrier signal at a carrier wavelength to generate one or more sidebands on the optical carrier signal; a radio frequency (RF) signal generator (104) operative to provide an RF drive signal to the optical modulator; a first optical waveguide grating (108) having a center reflection wavelength corresponding to the sidebands; and an optical circulator (106) configured to direct the optical carrier signal and the one or more sidebands into the first optical waveguide grating and to direct a reflected optical signal from the first optical waveguide grating towards an output to form an output optical signal, wherein the RF signal generator is operative to switch the drive signal on and off to form an intensity modulated output optical signal.

The utility model relates to the technical field of acoustics, and discloses an acoustic assembly comprising a waveguide grating, an internal mounting plate is fixedly connected in the waveguide grating, an internal clamping groove is arranged at the bottom of the waveguide grating, an internal clamping cover is clamped in the internal clamping groove, a filling block is fixedly connected in the internal clamping cover, and an external mounting plate is arranged in the internal clamping cover. A magnetic steel assembly is clamped in the waveguide grating, a limiting groove is formed in the bottom of the magnetic steel assembly, an acoustic assembly is clamped on the surface of the internal mounting plate, and a vibrating diaphragm is mounted at the top of the magnetic steel assembly. According to the utility model, through the arrangement of the diffusion members, the sensitivity of the soft material dome high pitch at the frequency band of 16000-20000 Hz is generally lower than that of other frequency bands, five groups of diffusion members corresponding to the frequency band of 16000-20000 Hz are arranged in front of the vibrating diaphragm, and the five groups of diffusion members form radians from the periphery to the center from large to small and correspond to the frequency band of 16000-20000 Hz, so that the sensitivity of the frequency band is effectively improved. The music performance of the high pitch of the soft ball top in the frequency band is obviously improved, and the installation work of the whole device is facilitated through the arrangement of the inner clamping groove.

The present application discloses a silicon-on-insulator array waveguide grating chip for dense wavelength division multiplexing, which relates to the field of integrated silicon photonics technology. The chip includes an AWG and a wavelength thermal tuning structure. The AWG is composed of an input waveguide, a first slab waveguide, an array waveguide, a second slab waveguide, and an output waveguide connected in sequence along the optical path direction. The AWG is used to implement wavelength division multiplexing and demultiplexing. The wavelength thermal tuning structure includes a thermal tuning electrode and a metal electrode. The thermal tuning electrode is located above the array waveguide and is connected to an external control circuit via the metal electrode. The thermal tuning electrode is used to heat the array waveguide according to an external voltage to achieve wavelength tuning of the AWG channel. As the voltage amplitude increases, the heat generated by the thermal tuning electrode increases, and the wavelength of the AWG channel drifts toward a longer wavelength. The technical solution of the present application can realize multi-wavelength dense wavelength division multiplexing on a compact chip, has the advantages of small size and high reliability, and can realize passband wavelength control through the wavelength thermal tuning structure to meet the application requirements of multi-wavelength optical networks.

The application discloses a dense optical fiber coding method based on an optical switch and a weak reflectivity grating string, and comprises the following steps: 1, a light source module emits a C-band pulse signal, and the signal contains optical pulses with different central wavelengths and overlapping in a time domain; 2, a weak reflectivity grating string is used to code each node to obtain different wavelength pulse combination types, and the coding signals of different coding nodes on the same link are spaced apart in the time domain; 3, the coding signal is injected into an array waveguide grating through an optical circulator, and is decomposed into more than one single-wavelength pulse signal; 4, a detector array and a collection card are used to carry out photoelectric conversion on the coding pulse signal, and the collected signal is output to an FPGA and an upper computer for processing and display; the problems that the prior art cannot be applied to realize real-time coding of a large-scale and high-reliability all-optical network and that the real-time coding scale is limited and cannot meet the use requirements of a large-scale network are solved.

The invention discloses an LPWG-based on-chip carrier envelope offset frequency detector and a self-beat frequency detection method. The detector comprises an ultra-short pulse port, a super-continuum spectrum SCG generation area, a long-period waveguide grating LPWG, a single-mode straight waveguide, an output straight waveguide, a coupling straight waveguide and a tuning electrode. The device is highly integrated, frequency beating can be completed only through one integrated waveguide chip, the problems that an existing detection method is high in cost, a system is complex, and a frequency beating system is difficult to operate are solved, a single chip is benefited to generate a cross-octave super-continuum spectrum and frequency doubling light at the same time, an extra frequency doubling crystal is not needed any more, and the device is simple in structure and convenient to operate. And due to the fact that the working bandwidth of the LPWG can limit the filtering effect, an external filtering element is not needed any more, and the successful research and development of the LPWG has wide application backgrounds in the aspects of high-precision frequency measurement, optical atomic clocks, stable and reliable on-chip optical frequency comb research and development and the like, and has important scientific significance and profound practical significance.

Systems and methods for waveguide gratings with adhesive for waveguide-based displays. The waveguide displays as described herein comprise an adhesive material configured to protect the grating structures from contaminants. The waveguide display as described herein can be manufactured with an inkjet printer.

A coupling device for a multi-channel optical fiber array and a multi-layer arrayed waveguide grating, includes: a first clamping component and a second clamping component. A plurality of optical fibers that are spaced apart in an X-axis direction are connected on the first clamping component, each optical fiber extends in a Y-axis direction, and a plurality of arrayed waveguide gratings that are spaced apart in the X-axis direction are connected on the second clamping component. Each arrayed waveguide grating extends in the Y-axis direction, the optical fibers and the arrayed waveguide gratings are disposed in a one-to-one coaxial mapping manner, each arrayed waveguide grating is right-trapezoid-shaped, and beveled surfaces of any two arrayed waveguide gratings are located on a same plane. A wavelength division multiplexing technology is combined with a multi-channel parallel transmission technology.

The invention provides an all-optical fast Fourier transform calculation implementation method and a photonic device. The method comprises the following steps: demultiplexing a time sampling vector based on a first array waveguide grating to obtain a parallel multi-wavelength signal; carrying out column-by-column phase modulation on the parallel multi-wavelength signals according to a discrete Fourier transform matrix based on a phase shift waveguide array to obtain weighted signals; and combining the weighted signals based on the second array waveguide grating to obtain an output optical signal. According to the method provided by the invention, a parallel multi-wavelength signal is obtained by demultiplexing a time sampling vector based on a first array waveguide grating; carrying out column-by-column phase modulation on the parallel multi-wavelength signals according to a discrete Fourier transform matrix based on a phase shift waveguide array to obtain weighted signals; and on the basis of the second array waveguide grating, weighted signals are combined to obtain output optical signals, the physical characteristics of high selectivity and low loss of an integrated photonic device are fully utilized, and efficient and high-fidelity Fourier transform calculation is realized in an integrated form with low structural complexity.

Anti-counterfeiting is benefited by integrating both optical and digital encoding-decoding approaches for spoof protection, e.g., in print anti-spoofing. An optical-digital encoding-decoding system uses an encoded medium, such as a security label, to display images encoded with digital data, and a decoding device to decode or decrypt the digital data for achieving stronger authentication in anti-counterfeiting or other security-related purposes. The images are encoded into resonant waveguide gratings (RWGs) in the encoded medium, enabling angle multiplexing of the displayed images and addressing different secrecy requirements in optically handling different groups of security-related data. Furthermore, aperiodic diffraction gratings instead of periodic ones are used in RWGs for selected images intended to be viewed by users, broadening beamwidths of outgoing light beams generated by these RWGs to allow the selected images to be more conveniently viewed by the users over a wider range of angle.

The invention discloses a waveguide grating filter based on an optical phase change material and a filtering tuning method, the waveguide grating filter comprises a substrate, a buffer layer and a phase change material layer, a waveguide grating structure is defined in the phase change material layer through an external energy field, and the waveguide grating structure comprises a core waveguide and periodic lateral gratings arranged on the two sides of the core waveguide. According to the invention, the reversible phase change characteristic of a phase change material is utilized, and a tuning method of writing-erasing-rewriting is adopted: laser is selectively irradiated on a phase change material layer to form a crystalline waveguide grating structure; the crystalline region is recovered to be in an amorphous state through heating or laser scanning, so that erasing is realized; and flexible regulation and control of the spectral response of the filter are realized by writing structural parameters such as the tooth width, the duty ratio and the core waveguide size of the dynamic tuning grating again through laser. The filter works in a communication wave band of 1.5-1.6 microns, and has the outstanding advantages of reconfigurable structure, non-volatile property, flexible tuning, simple manufacturing and the like.