33results about How to "Enables tunability" patented technology

The invention discloses a production method of an optical microwave signal with tunable broadband frequency. The method comprises the following steps: constructing a stable dual-loop low-frequency optoelectronic oscillator; injecting an external continuous lights into the optoelectronic oscillator, implementing the injection locking in a directly modulated laser of a core component of the optoelectronic oscillator to finish the up-conversion process of the optical microwave so as to generate a high-frequency optical microwave signal; implementing the tunability of the optoelectronic oscillator by adjusting the wavelength, optical power and polarization state of the external continuous lights so as to generate the optical microwave signal with needed frequency. By injecting the external continuous lights into the directly modulated laser in the optoelectronic oscillator and then locking an optical carrier wave after the up-conversion is generated under a high-order mode, the high-quality optical microwave signal is produced. The method provided by the invention can be used for producing any high-frequency optical microwave signal based on an injection locking technology by using the lower-frequency electric signal, and the tunability of the microwave frequency can be realized by only controlling the wavelength, polarization state and optical power of the injected continuous lights.

The invention provides an adjustable metamaterial based on working frequency and a production method thereof, wherein the production method comprises the following steps that: groove arrays are processed on a base material, and micropores which are communicated with the outside are processed on the inner walls of all the grooves; and two pieces of base materials are bonded with each other, so the grooves are correspondingly bonded to form a hollow cavity body, liquid crystal is injected into the hollow cavity body through the microspores, so the metamaterial is obtained. Because the dielectric constant of the liquid crystal is changed along with the variation of the temperature or the electric field of the outside, the working frequency of the metamaterial can be selected within a larger range, and the tunability within a certain frequency range is realized; and the metamaterial can be used as a focusing lens, a resonant cavity and the like for microwaves and radio-frequency bands.

A tunable QWIP FPA device that is configured for spectral tunability for performing the likes of imaging and spectroscopy is disclosed. A selected bias voltage is applied across the contacts associated with a particular detector layer/channel of the device, where each applied bias corresponds to a particular target spectrum/color for detection. Each detector layer/channel can be coarse tuned for a bimodal or dual-band operation (e.g., MWIR/LWIR). Also, each detector layer/channel is configured for continuous or fine tuning within a particular mode (e.g., MWIR/MWIR). Thus, dynamic bias-controlled tuning is enabled. Asymmetric quantum well configurations enable this tunability.

The invention discloses a micro-ring resonant cavity tunable optical filter based on liquid crystal slit waveguides. The micro-ring resonant cavity tunable optical filter comprises a substrate, a first straight waveguide, a second straight waveguide, a micro-ring waveguide, a first electrode, a second electrode and an upper wrapping layer. The first straight waveguide and/or the second straight waveguide are/is internally provided with slit structures or a slit structure, the first straight waveguide and the second straight waveguide are respectively arranged on the upper surface of the substrate, a slit structure is arranged in the micro-ring waveguide, the micro-ring waveguide is arranged on the substrate and located between the first straight waveguide and the second straight waveguide, the first electrode is arranged in an inner circular ring region of the micro-ring waveguide, and the second electrode is arranged in an outer circular ring region of the micro-ring waveguide. The first straight waveguide, the second straight waveguide, the micro-ring waveguide, the first electrode and the second electrode are respectively covered with the upper wrapping layer, and the slit structures are filled with the upper wrapping layer. The micro-ring resonant cavity tunable optical filter has the advantages of being low in control voltage, large in resonant wavelength tuning range and simple in structure.

The invention discloses a tunable frequency doubled optoelectronic oscillator device based on phase modulation, relates to the technical field of a microwave and the technical field of optical communication, and is mainly applied to generation of a microwave local oscillator signal. The method is as shown in attached graphs. The device comprises a laser source, polarization controllers, a circulator, a polarization beam splitter, a phase modulator, an optical coupler, polarizers, a standard single mode fiber, optoelectronic detectors, a tunable bandpass filter, an electric amplifier and an electric phase shifter. The phase modulator is characterized in that modulation is carried out in a forward direction and is not carried out in a backward direction. An optical signal output from the circulator is split into two ways of signals with equal power through the optical coupler. One way is fed back to the phase modulator to form an optoelectronic oscillator, thereby obtaining a fundamental frequency signal. According to the other way, an optical carrier is inhibited by adjusting the polarization controller, thereby obtaining a frequency doubled microwave signal. Through combination of the tunable bandpass filter, the frequency doubled microwave signal with tunable frequency can be obtained. According to the optoelectronic oscillator, the frequency tuning range is relatively large, the phase noise is relatively low, and moreover, the fundamental frequency oscillator signal and the frequency doubled microwave signal can be obtained. The scheme is simple in structure and flexible in adjustment and is not influenced by bias voltage drift in a traditional strength modulation scheme.

The invention discloses a reconfigurable optical filter based on a micro-ring array, and belongs to the technical field of optical fiber communication and integrated photonics. The filter comprises afirst bus waveguide, a second bus waveguide and a plurality of micro-rings; the plurality of micro-rings are connected in parallel by the first bus waveguide and the second bus waveguide; the plurality of micro-rings are arranged between the first bus waveguide and the second bus waveguide at equal intervals; coupling regions are arranged between the micro-rings and the first bus waveguide; coupling regions are arranged between the micro-rings and the second bus waveguide; coupling regions are arranged between adjacent micro-rings; each coupling region is provided with a reconfigurable opticalcoupler, and the on-off state of the reconfigurable optical coupler can be independently regulated and controlled. The optical coupler structure with the reconfigurable on-off state is introduced into the coupling regions of the micro-ring array, whether the coupling action occurs in each coupling region or not can be independently controlled, various topological structures can be realized in theone-dimensional micro-ring array by designing and combining the on-off states of all coupling regions, and the diversity of a filtering function is realized.

The invention provides a dual-frequency Faraday semiconductor laser which comprises a laser diode (1), a collimating lens (2), a Faraday atomic filter and a laser cavity mirror (7).The Faraday atomicfilter comprises a first polarization splitting prism (3), an alkali metal atomic gas chamber (4) and a second polarization splitting prism (5). The output light of the laser diode (1) is incident into the alkali metal atom gas chamber (4) and then two laser modes are selected. The angle between the laser cavity mirror (7) and the incident light is adjusted so that the reflected light of the lasercavity mirror (7) returns to the semiconductor laser diode (1), oscillates in the resonant cavity and amplifies to exceed the laser oscillation threshold so as to output dual-frequency laser light atthe first polarization splitting prism or the second polarization splitting prism. The tunability of the output frequency of the dual-frequency semiconductor laser can be realized by changing the temperature and magnetic field conditions of the atomic gas chamber, and the transmission spectrum contains two stable transmission peaks with similar transmittance so as to work stably for a long time.

The invention discloses a preparation method of a liquid crystal elastomer film, a tunable filter and a preparation method of the tunable filter. The preparation method of the liquid crystal elastomerfilm comprises the following steps: mixing and stirring a liquid crystal monomer, a cross-linking agent and a photoinitiator to obtain a liquid crystal elastomer mixed solution, performing friction orientation on the two glass plates spin-coated with orientation layers in the same direction, bonding the two glass plates according to the friction orientation direction at a preset distance intervalto obtain a liquid crystal box, pouring the liquid crystal elastomer mixed solution into the liquid crystal box, and carrying out ultraviolet exposure to make the liquid crystal elastomer mixed solution fully polymerize, thereby obtaining the liquid crystal elastomer film with uniform molecular orientation. According to the embodiment of the invention, the tunability of the optical filter is realized.

The invention provides a multi-wavelength non-atomic resonance Faraday semiconductor laser. The laser comprises a laser source, a collimating lens, a Faraday atom optical filter and a reflector (6) which are sequentially arranged on an optical path; the laser source comprises a first laser light source (1) and a second laser light source (1a); an atom air chamber (4) contains a first alkali metalatom and a second alkali metal atom; a permanent magnet (5) applies a static magnetic field to the atom air chamber (4), and therefore, the magnetic field intensity in the atomic gas chamber (4) is uniformly distributed in the axial direction and non-uniformly distributed in the radial direction, and the magnetic field intensity on each emergent light path corresponds to the magnetic field intensity which is required by a corresponding wavelength transmission spectrum of a Faraday atomic filter only contains one non-atomic resonance transmission peak. According to the laser of the invention, through the optical filter with the non-uniform magnetic field, multiple beams of light respectively pass through corresponding magnetic field areas on respective optical paths, so that different magnetic field intensities can be obtained, and multi-wavelength laser output without interference light is realized.

The invention relates to a free opening and closing system for a local hollow light beam based on an optical tweezer technology. The free opening and closing system comprises a laser source, a beam expander, a circular hole diaphragm, an axicon and a focusing lens which are sequentially arranged in the light propagation direction. Laser emitted by the laser source passes through the beam expander;the asymmetric light beam after regulation and control is refracted by the axicon and is focused by the focusing lens to form a local area hollow light beam with a notch, the rotating circular hole diaphragm is recovered, and the incident light beam passes through the optical system to form a three-dimensional closed local area hollow light beam. By flexibly rotating the circular hole diaphragm and regulating and controlling the incident light beam, the formed local hollow light beam notch can be freely opened and closed, a new thought is provided for particle capture of an optical tweezer system, the limitation of an existing optical tweezer device is solved, and the characteristics that the system is easy to operate, tunable and stable can be achieved.

The invention provides a tunable multitapped microwave photonic filter capable of combining the technical advantages of a coherent system and an incoherent system, and belongs to the field of microwave photonics. The core part of the filter is an optical delay line module based on a coherent system single optical wavelength and an incoherent system multi-mode optical fiber, the single optical wavelength lowers cost and simplifies a system; the multimode optical fiber provides mode dispersion and generates a time delay between modes, a spatial wavelength division multiplexing delay line structure provided by the multimode optical fiber eliminates an optical coherence phenomenon, an the microwave photonic filter is endowed with a high resolution and flexible frequency response characteristics. In addition, on the basis of a slit mask plate, the light beam incidence angle of an incidence multimode optical fiber can be regulated to realize the tunable characteristics of a filter tap, and the light beam number of the incidence multimode optical fiber can be changed to realize the variable characteristics of a filter tap number. The filtering experiment of the filter displays that a waveinhibition rejection ratio can be above 30dB, and stability is good.

The invention discloses a preparation method of an S/C dual-band multilayer tunable frequency selective surface, and belongs to the technical field of dual-band frequency selective surfaces. The invention aims to solve the technical problems of poor low-and-medium-frequency wave-absorbing performance and single working frequency of the existing frequency selective surface. The method comprises the following steps: 1, adding polyvinyl butyral powder into absolute ethyl alcohol, performing stirring at room temperature by using a magnetic stirrer until the solution is transparent, then adding different dosages and types of powder, tributyl phosphate and dibutyl phthalate, performing stirring again to obtain turbid liquid, and then carrying out film casting, drying or air drying to obtain a plurality of thin films; 2, respectively performing engraving, and obtaining a honeycomb structure on the film to obtain a plurality of single-layer frequency selective surfaces; 3, stacking together according to different modes, respectively testing the wave-absorbing performance, drawing a reflection loss curve graph, and summarizing the change rule of the wave-absorbing performance. The method has a good stealth effect on radar wave detection of S and C wave bands.

The invention discloses a tunable reflective phase shifter based on ferroelectric materials, which comprises a plurality of tunable phase shifting units, and each tunable phase shifting unit comprises an input node, an output node, a quadrature coupler, a first reflective load unit and a second reflective load unit. The first reflective load unit and the second reflective load unit are respectively composed of two inductors and a tunable capacitor, the tunable capacitor comprises a substrate and a metal electrode, the substrate and the metal electrode are rectangular, the metal electrode is stacked on the substrate and completely coincides with the substrate, and the metal electrode is provided with an S-shaped groove extending from the front end to the rear end. The S-shaped groove penetrates through the metal electrode from top to bottom, the S-shaped groove is filled with a barium strontium titanate material, the bottom of the barium strontium titanate material is attached to the substrate, and the left end face and the right end face of the metal electrode are the two ends of the first tunable capacitor. The tunable reflective phase shifter has the advantages of simple structure, small size, low cost, small insertion loss and high working frequency.

The embodiments herein provide a method and a system for generating and regulating local magnetic field variations required for spin qubit manipulation based on scalable quantum processors using micro-structures in integrated circuits. In an embodiment the system provides an adaptive and independent magnetic-field control to each qubit on a hardware substrate and comprises several micro/nano-scale current-carrying structures near a qubit for controlling and manipulating the qubit using the locally generated variable magnetic field, in-turn controlled by the tunable current flowing through these structures. The current-carrying structures in conjunction with fast current control provides fast switching/tuning of magnetic fields for rapid adiabatic passage control of one or more qubits simultaneously. The tenability of the qubits allows post-fabrication setting of adaptive magnetic field strengths and frequency separation of qubits thereby enabling the qubits to simultaneously realize their intended control signals without any added disturbance from neighboring qubits.