Density functional theory (DFT) and time-dependent density functional theory (TDDFT) at the B3LYP/6-311+G(d, p) level were used to calculate and optimize the physical characteristics of 4-bromophenol under the different electric fields, including the bond length, bond angle, total energy, dipole moment, energy gap, infrared spectrum, dissociation properties, and excited state. The results revealed a significant change in the molecular structure of 4-bromophenol under an external electric field (0-0.03 a.u.). The molecular C—Br bond length, O—H bond length, and dipole moment increased gradually with increasing external electric field, while the C—O bond length, total energy, and energy gap decreased gradually. The four absorption peaks of the molecular infrared spectrum showed a red shift. Simultaneously, the first 10 excited states also showed a red shift. When the external electric field intensity was 0.03 a.u., the potential barrier disappeared, and molecular dissociation was observed.

Based on electro-optical sensor array, the accuracy of space objects precise orbit determination (POD) and orbit prediction (OP) are studied in this paper for the wide field-of-view photoelectric telescopes. The reference orbit of Jason-3 and Cryosat-2 obtained by using satellite laser ranging data from the International Laser Ranging Service, which are used to analyze the POD and OP accuracy of the wide field-of-view photoelectric telescope observations. The calculation results show that the POD root mean square (RMS) position error of the wide field-of-view photoelectric telescope observation data is better than 250 m and the RMS of the velocity error is less than 0.25 m/s. The accuracy of the 3-day orbit prediction based on the POD results is better than 20". The results indicate that the wide field-of-view photoelectric telescope can not only improve observation efficiency, but also obtain accurate orbit information of space objects through post-processing of its observations, which can provide data support for related work and space missions with orbit information.

With the continuous progress of science and technology, people have put forward higher requirements for indoor positioning services. For the problems of low positioning accuracy, complex and expensive equipment of traditional indoor positioning technology, a multi-light-emitting diode (LED) indoor positioning method based on extreme learning machine (ELM) neural network is proposed in this paper. First, the optical power of LEDs at each reference point and the position coordinates of the photodetector are used as fingerprint data to construct a fingerprint database. Then, the fingerprint database is introduced into the ELM neural network model for training, and the light intensity-based localization model is established. The simulation results show that the time for training the data set of the method is only 0.0687 s in a localization area of 4 m×4 m×3 m, and the average localization accuracy can reach 1.17 cm.

By studying the core holographic optical elements in the holographic plate waveguide display system, we prepare a reflective volume holographic grating with refractive index modulation on a holographic plate with quartz glass as substrate and dichromate gelatin as recording medium. The effects of different exposure intensity, refractive index modulation and water washing time on diffraction efficiency of grating are researched. Experimental results show that the diffraction efficiency of reflective volume holographic gratings can be improved by using 441.6 nm He-Cd laser light source and complex post-treatment process. The diffraction efficiency of reflective volume gratings can reach 61.8%. Under the condition of visible light incident, a remarkable light splitting effect is produced. The prepared holographic experimental sample can be transmitted by waveguide under the condition of total reflection, which provides a method to improve the diffraction efficiency of display devices such as head mounted display device and augmented reality during transmission.

Fiber Fabry-Perot tunable filter (FFP-TF) is one of the core components of the fiber Bragg grating sensor demodulation system. Its stability is very important to the demodulation accuracy, and the temperature drift is the influence one of the key factors of its stability. The nonlinear mapping ability of the least squares support vector machine (LSSVM) can effectively compensate for drift. In this paper, aiming at the problem that the traditional LSSVM model parameter selection is easy to fall into the local optimum, based on the improved beetle search particle swarm optimization algorithm to find the optimal penalty factor and kernel parameters of the LSSVM model in the global scope. The experimental results show that using the optimized LSSVM to compensate the temperature drift of FFP-TF can reduce the temperature drift error from the maximum amplitude of 1025.21 pm to ±3.03 pm, and improve the temperature stability of FFP-TF demodulation in a variable temperature environment.

Highly nonlinear photonic crystal fiber has the characteristics of small core and large refractive index contrast. In this work, the photonic crystal fiber (PCF) with a special structure based on Bi2O3-GeO2-Ga2O3 core glass material was designed. Using full-vector finite element method while the perfect matched layer boundary condition, the birefringence coefficients of the PCF at the wavelengths of 1.55 μm and 1.80 μm are 2.89×10-2 and 3.28×10-2, respectively. The dispersion curve shows, when the ellipticity of the inner cladding elliptical air hole is 0.6, the photonic crystal fiber with structural parameters M=d/Λ of 0.5 and 0.6 has two zero dispersion points, indicating it has negative dispersion characteristics. The limiting losses of X polarization and Y polarization at 1.55 μm are 3.8784×10-5?4.5739×10-5 dB·km-1 and 3.5203×10-5?4.2147×10-5 dB?km-1, respectively. This work provides reference for nonlinear optical fiber fields such as optical communication and microstructure optical fiber sensor.

To study the transmission ability of hollow-core anti-resonance fiber, a mid-infrared laser transmission experiment was carried out using a self-made nodeless hollow-core anti-resonance fiber from 2.6 μm to 4.35 μm spectral region. The fiber cladding consists of seven silica capillary tubes, the average wall thickness is 800 nm, the outer diameter of the fiber is 365 μm, and the core diameter is 115 μm. A tunable mid-infrared source was used as a broadband light source. The laser propagation capability of the fiber at 2.60 μm, 3.27 μm, 3.41 μm, 3.80 μm, 4.08 μm, 4.21 μm, and 4.35 μm was tested. And the transmission loss at this spectral region of the fiber was measured. Results show that the fiber can realize low-loss light guide from 2.6 μm to 4.08 μm band, with the lowest transmission loss of 0.037 dB/m at 3.27 μm. The transmission loss of the fiber is 3.200 dB/m at 4.08 μm and 0.788 dB/m at 4.35 μm, where the attenuation of bulk silica is 1000 dB/m and 3000 dB/m, respectively. Hollow-core anti-resonance fiber has great potential in the application of mid-infrared laser flexible delivery.

In petroleum exploration, a seismic geophone is an indispensable tool. It is primarily used to collect seismic wave data, obtain formation data, and monitor reservoir exploration and fracturing oil recovery technology. This study investigates distributed fiber-optic acoustic sensing (DAS) system and its application in petroleum geology exploration, and deeply analyzes the interferometric demodulation principle, the algorithm, and the parameter test of DAS technology. Furthermore, a ground geophysical prospecting test is conducted, and a clear seismic section image is generated, as well as the performance and the test data of DAS are analyzed in detail.

Due to its miniaturization, integration, and fast detection speed, the miniature optical fiber spectrometer was suitable for on-line detection of multi-component substances in industrial sites. In view of the problem that the micro spectrometer was affected by the stray light, photometric noise and light source fluctuation, the measurement accuracy of the spectral signal was poor, and an optical system error correction method was proposed for on-line detection of micro spectrometer. Firstly, a micro spectrometer was used to measure the spectral intensity online, and the spectral signal was obtained from the reference solution and the solution to be measured. Secondly, the adaptive wavelet threshold denoising method was used to eliminate the photometric noise of the spectral signal and improve the sensitivity of the spectral signal. Then, a light source stabilization method based on the invariance of the dual wavelength light intensity ratio was proposed to dynamically eliminate the light source error. Finally, the spectral signals of the copper and cobalt were dynamically corrected, and the performance analysis of the correction curve was performed. The results show that the method proposed in this paper is simple and fast, and it was suitable for dynamic correction of spectral signal to meet the needs of online detection of multi metal impurity ions.

In the context of satellite terrestrial radio frequency/laser wavelength sharing, this paper studies the aggregate interference of International Mobile Telecommunication System (IMT) terrestrial stations that is imposed to the low earth orbit (LEO) satellites equipped with the multi-beam receiving antenna for radio communication with frequencies below 6 GHz and free-space laser communications. For frequencies below 6 GHz, typical kinds of IMT base station deployment scenarios were emulated according to the latest International Telecommunication Union (ITU) Recommendations. By means of Monte Carlo simulation, a statistical clutter loss model was introduced into the interference simulation. The model's applicability was analyzed, and it was used for the random detailed scene simulation. After combining the typical scenarios with the characteristics of the satellite multi-beam antennas, we study the change trends of the different typical base station deployment scenarios with the different satellite antenna beam scanning angels by simulations. The results show that when the height of base station antenna was below rooftop, the clutter loss should not be neglected. On the other hand, we analyze the possible interference of the terrestrial free-space optical communication imposed to the LEO satellite by link calculation. The analysis results have theoretical guiding significance and application value for monitoring the receiving environment of LEO satellites.

The high bandwidth, low latency, and low power consumption of the on-chip optical interconnection can effectively alleviate the communication bottleneck of the electrical interconnection mode in a multicore processor. On-chip optical router is an essential part of the on-chip optical network design. With the gradual increase in processor scale, the traditional 4-port and 5-port can no longer meet the existing network density requirements. Additionally, with the expansion of the optical interconnection network, the problems such as communication congestion and low utilization of microring resonators have appeared. Therefore, this study proposes an 8-port on-chip optical router LONE to realize arbitrary communication between 8-port without blocking. OMNET++ simulation results show that LONE improves the utilization of microring resonators compared to optical routers of the same scale. Furthermore, the number of microring resonators is reduced by more than 41.67%, and insertion loss is reduced by more than 27.05%. The cost also has certain advantages, and the area overhead is reduced by more than 10%. Simultaneously, the biggest feature of the LONE structure is its simple structure, easy expansion, and adaptability to the needs of high-density networks.

The influence of internal loss and internal quantum efficiency on the output power of the laser is theoretically analyzed, and the comprehensive optimization design of the 852 nm Fabry-Perot (FP) laser is carried out by using PICS3D software. The designed device has the characteristics of small far-field divergence angle, low internal loss, and high internal quantum efficiency, which can achieve stable and high power output under large current. The basic transverse mode 852 nm FP laser was fabricated with internal loss less than 1 cm-1, divergence angle of fast axis is 42.3°, divergence angle of slow axis is 5.6°, and unilateral output power of 115 mW without coating. The theoretical and experimental results show that while increasing the thickness of the waveguide layer and non-doping the waveguide can reduce the absorption of light caused by carriers and reduce the internal loss of the laser. By increasing the component of Al and the doping concentration in the AlGaAs material, the carrier leakage can be effectively suppressed and the high internal quantum efficiency can be ensured.

H13 steel has often been used as a hot-work die material. However, it tends to undergo failure because of wear and crack generation under high-temperature and high-pressure working conditions. Laser cladding is an effective remanufacturing method for such materials. However, the temperature gradient and cooling rate of the formation process are very large owing to rapid cooling and heating characteristics, often inducing excess thermal stress and cracking of the coating. Herein, a numerical simulation of a laser cladding 316L/H13+20%WC composite coating on H13 steel surface was performed. The variation in the temperature gradient and cooling rate with time and the influence of substrate preheating on the temperature gradient and cooling rate were studied. Moreover, to verify the numerical simulation results, a laser cladding formation test of the composite coating was conducted on the H13 steel substrate. Experimental results show that substrate preheating can significantly reduce the temperature gradient and cooling rate on the top surface of the coating and exerts a certain restraining effect on the cracks of the sample surface. The findings of this study provide a reference for the laser cladding modification and repair of H13 steel dies.

Fog water collection is the process of converting gaseous fog into liquid water,which has important research value. The control of condensation efficiency is crucial factor in the collection of fog water. Improving condensation efficiency is mainly related to the thickness of the boundary layer and effective renewal on the substrate surface. In this paper, inspired by the back structure of desert beetles, a Janus film with bump structure on the surface of aluminum foil is prepared by femtosecond laser micro-nano processing and surface chemical modification, which could achieve efficient droplet condensation. The experimental results show that compared with the flat Janus film, the water collection efficiency of the bumpy Janus film is increased by 80%. More importantly, the bumpy Janus film can capture a horizontal fog flow and adapts harsh natural environment.

Photonic crystal surface emitting lasers (PCSELs) have the advantages of high power and high beam quality because they can achieve large area single mode lasing. They have important application prospects in optical communications, laser radar, laser printing, laser display, and laser processing. This paper focuses on the analysis of the band-edge lasing principle and threshold gain of the photonic crystal laser with in-plane multi directional distributed feedback effect, and combines the semiconductor laser rate equation to deduce the output optical power formula of PCSELs, and also gives some effective methods to increase the optical power of PCSELs. The research results can provide theoretical guidance for the development of high performance PCSELs.

Because of its good mechanical and electrical insulation properties, silicone rubber has various applications. However, in a low-temperature environment, the ice coating on its surface severely limits its application. In this paper, a laser engraving machine was used to process a series of micron-sized cylindrical textures on the surface of a composite insulator umbrella skirt, resulting in a superhydrophobic surface that required no chemical modification. Three-dimensional topography instruments and a scanning electron microscope were used to observe the surface morphology of the samples. The adhesion measurement device was used to assess the ice adhesion of textured silicone rubber surfaces under various operating conditions. A high-speed camera was used to capture the condensation-melting process of droplets on the surfaces of various textured silicone rubber. The results show that under certain working conditions, the cylindrical texture sample with the processing power of 35 W and texture diameter and spacing of 350 μm exhibits the best hydrophobicity and the lowest adhesion, and the best anti-icing performance. Friction tests confirm that the surface texture of the processed silicone rubber has certain ice-repellent durability and stability.

Using a semiconductor laser subjected to optical feedback from cascaded chirped fiber Bragg gratings (CFBGs), we propose and demonstrate a method for generating wideband chaos without a time-delay signature (TDS). The high dispersion of cascaded CFBGs creates irregular external-cavity modes and destroys the resonance of external-cavity mode, eliminating the TDS of the chaotic signal. In addition, the irregular external-cavity modes beat with the internal-cavity modes of the laser, introducing new high-frequency oscillations, which enhances the bandwidth of the chaotic signal. The effects of the dispersive optical feedback strength and wavelength detuning between the laser and CFBG on bandwidth and TDS in feedback systems with single CFBG and cascaded CFBGs were compared in the experiment. The obtained results show that the feedback system with cascaded CFBGs exhibits better performances in bandwidth improvement and TDS suppression under strong feedback and negative wavelength detuning conditions. Finally, we experimentally obtained a TDS-free chaotic signal with a 3 dB bandwidth of 12 GHz.

DP590 dual-phase steel and 6016 aluminum alloy were used as test materials. A laser deep fusion welding test was conducted using Ti powder in the lap mode of "steel at the top and aluminum at the bottom," and the microstructure and properties of the joint before and after adding the Ti powder between them were compared. The test results show that under a laser power of 1600 W, a welding speed of 35 mm/s, a defocus amount of +1.0 mm, and back protection using the Ar protective gas of 15 L/min, the welding quality is improved by the addition of the Ti powder, and the average line load is 110 N/mm, which is 10% higher than the condition without the addition of the powder. The addition of the Ti powder can refine the grain size. During the welding process, the Ti powder will be absorbed into the liquid aluminum and react with Fe to form a ductile phase Fe2Ti, which will improve the property of weld-joint.

In this paper, a new concept of few-mode waveguide is proposed. Based on the plane-wave expansion method and the finite-difference time-domain method, this concept is demonstrated in the Kagome lattice line defect structure. By changing the parameters of defective dielectric columns (radius, location) and inserting new defective columns between original medium columns, a two-mode Kagome lattice waveguide structure with a bandwidth of 0.08888ωa/2πc is obtained. This few-mode waveguide structure provides a new idea for the design of photonic crystal planar waveguide and will have important application value in photonic integration and other fields.

The nonreflective high-transmittance transmission phenomenon was first discovered for the transverse magnetic wave between two interfaces; this is known as the Brewster effect. However, all high-transmittance phenomena observed so far are subject to a single frequency or angle of incidence. In this study, a terahertz metasurface that can achieve a dual-frequency angle-independent high transmittance is designed and fabricated. The angle-independent high transmittance can be realized depending on the strict match between the longitudinal wave impedance of the metasurface and air. Simulation, theoretical analysis, and experimental results are consistent with each other, proving the design feasibility. The proposed method can be extended to other frequencies; thus, a wide range of applications can be achieved, including ideal filters and spatial phase shifters.

A three-dimensional TC17 thick-walled part was formed on a TA0 substrate using point-mode forging laser deposition technology. Its deposited and annealed structure and mechanical properties were analyzed using an optical microscope, scanning electron microscope, uniaxial tensile test, and microhardness test. The results show that the original macroscopic grains have an equiaxed morphology, and the grains' interiors are formed by numerous primary fine α laths, few equiaxed α phases, and β transformation structures. The uniaxial tensile test was performed at room temperature along the deposition height direction and vertical deposition height direction. Tensile strength in both directions exceeded the national standard for forgings in the annealed state. The hardness test shows that the original deposition area has a Vickers hardness of ~400 HV, and the hardness exhibits a downward trend as the temperature increases. The uniaxial tensile test results show that the strength and plasticity in both directions significantly reduced after annealing at 850 ℃/1 h. After annealing at 610 ℃/1 h, the material's strength is significantly increased, and the plasticity is significantly reduced. After annealing at 730 ℃/1 h, the sample's strength in both directions is slightly reduced compared with the deposited state, but its plasticity is improved. The scanning electron microscope photos show that the tensile fracture dimples formed after 730 ℃ treatment are deep and dense, indicating toughness fracture.

Terahertz absorbers can be widely used in research fields such as military equipment and sensing instruments. Therefore, a polarization-insensitive terahertz metamaterial absorber with a fourfold symmetrical structure is proposed, and the absorption mechanism and influencing factors of the structure are analyzed by changing the structure size and current distribution in this paper. Experimental results show that the resonance frequency of the absorber is in the terahertz frequency band and the absorption rate can reach 99.98%. In order to make the application range of the terahertz absorber wider, two polarization-insensitive terahertz absorbers with adjustable frequency are further proposed. The simulation results of the electromagnetic simulation software CST show that the terahertz metamaterial absorber has high absorption rate, good frequency adjustment performance, and is insensitive to polarization angle, which has great application research significance.

In order to avoid the high manufacturing cost and ohmic loss of metal perfect metamaterial absorber (PMA), and to solve the problem that PMA is sensitive to the polarization state and incident angle of light. A dual channel polarization independent dielectric narrow-band PMA is designed by using low loss dielectric materials, and the theoretical analysis and verification are carried out by using the finite-difference time-domain method. It is found that the absorption wavelength, absorption efficiency, and full-width at half-maximum of the polarization independent medium narrow-band PMA designed in this paper are the same no matter in transverse electric(TE) or transverse magnetic (TM) polarization state. TM and TE polarization can achieve narrow bandwidth and ultra-high absorption at the same wavelength because PMA structure is rotationally symmetric. The reason why PMA can achieve dual channel narrow bandwidth is that Fabry-Perot cavity resonance and guided mode resonance are formed in PMA grating respectively. This research can provide theoretical guidance for the preparation of high quality polarization independent medium narrow bandwidth PMA in the future.

In order to meet the needs of large-capacity data transmission and equipment miniaturization of communication equipment, a multi-mode reconfigurable terahertz microstrip antenna including rectangular chip, media substrate and slotted floor is proposed in this paper. Based on the electrically controllable characteristics of graphene materials in the terahertz band, 3 groups of graphene are distributed as regulator switches in the slotting, and the switch is switched off by controlling the bias voltage of graphene. The antenna has 6 frequency reconfigurable modes, the resonant frequency is distributed in the range of 2.652-4.565 THz, the -10 dB bandwidth is greater than 10%, the maximum radiation gain is 2 dBi, and the reflection coefficient is lower than -15 dB, showing good radiation characteristics. The use of a single group of graphene as a fine-tuning control unit can realize the tunable function of the antenna in the small frequency range, which has great application potential in the design of graphene terahertz reconfigurable antennas and antenna arrays.

The temperature distribution and variation of HT250 gray cast iron during laser remelted are analyzed by establishing a three-dimensional transient simulation model, and the influence of laser power on the temperature field of laser melting pool is discussed. The geometric characteristics and microstructure of laser remelting single channels are observed by metallographic microscope and scanning electron microscope, respectively. The microhardness of the channel's cross section is measured by the microhardness tester. The results show that the remelted zone is semi-arc. From the surface to the inside, the remelted zone, the heat affected zone and the base metal are in turn. With the increase of laser power, the peak temperature of laser molten pool increases, the depth increases, and width of melt track deepens. The calculated geometry of the laser melted pool is in good agreement with the actual measurement of the laser melted pool, which proves that the model is reliable and effective. In addition, the experimental results show that the main microstructure of the HT250 gray cast iron in the remelted zone is very small dendritic modified ledeburite. The average microhardness of the remelted zone is about 1000 HV, which is about 5 times higher than that of the substrate.

Based on the "blackout", the physical model of "free space-plasma layer-free space" is established. On the basis of this model, the analytical method is used to simulate and study the relationship between plasma absorption rate and electromagnetic wave frequency under the premise of different thickness plasma layer. The absorption of left-handed and right-handed circularly polarized waves by plasma layer and the one-way attenuation of electromagnetic waves in plasma were studied by changing the electron density, external magnetic field intensity and electron collision frequency, respectively. The results show that the absorption characteristics and one-way attenuation of electromagnetic waves by plasma change with the change of plasma layer thickness, electron density, external magnetic field strength, and electron collision frequency. The simulation results can be used as a reference for reducing the absorption rate of plasma layer and alleviating the problem of the "blackout".

An optimized method for the design of progressive addition lens (PAL) is proposed in this study, aiming at the characteristics of the population that experiences a transition from myopia to presbyopia. The height expression of the surface of the PAL is proposed based on an aspherical formula, and a continuously varying conic coefficient is used to adjust the optical power and astigmatism distribution. Two PALs with an additional power of 1.5 dioptres were designed for comparison, using the spherical height and the aspheric height expression, respectively. The optical power and astigmatism distribution are given in the design results, and the free form verifier (FFV) of ROTLEX Ltd. in Israel is used to verify the results obtained via simulation. The results show that the optical power around the assembly centre of the optimized PAL annularly increases. The maximum astigmatism distribution of the lens does not exceed 1.25 dioptres, thereby not exceeding 83% of the additional power. In the area above the assembly centre, the astigmatism at any position is less than 0.5 dioptres. The length of the power stabilization zone in the near zone is approximately 20 mm. The optical power of the distance zone of the optimized PAL is annularly increased, which is beneficial to alleviate the asthenopia of myopia. The maximum astigmatism of the lens is considerably reduced, which is easily accepted by customers whose defect in vision has changed from myopia to presbyopia and wear PALs for the first time.

The ring resonator can be used for high precision and high sensitivity sensing. In this paper, the ring resonator is combined with cantilever pressure sensor. The expression of sensitivity of this pressure sensor is derived, the sensitivity will vary with the applied pressure. When the pressure is 1 kPa, the sensitivity is 71.73 pm/kPa. Lithium niobate on insulator (LNOI) which has low loss is used to design ring resonator to obtain a pressure sensor with high Q. It can improve the accuracy of pressure measurement. The effects of critical coupling and non critical coupling, waveguide loss and the perimeter of the ring waveguide on Q factor are discussed and analysed by Matlab. The results show that the most important factor is the waveguide loss. The increasing of the perimeter of the ring waveguide will not increase the Q factor directly, but will reduce the loss and increase the Q factor indirectly. The results show that when the radius of the ring waveguide is 80 μm and the waveguide loss is 0.6322 m-1, Q factor can reach 5.7×106.

Multi-beam antenna technology can be used to improve the utilization of spectrum resources and channel capacity, which has attracted much attentions. Transformation optics has been widely used to design various kinds of antennas and has become a research hotspot in recent years. In this paper, an area mapping method was initiatively proposed to design a multi-beam lens antenna. The implementation method was discussed. The performance of the antenna was verified by simulation. Research results show that the designed multi-beam lens antenna based on the area mapping method can exhibit a nonmagnetic and piecewise homogeneity material parameter distributions, and can be synthesized by drilling hole in the dielectric substrate or using equivalent medium. The proposed multi-beam lens antenna can be used to reshape the radiation direction of the dipole antenna, improve the radiation gain, and achieve multi-directional radiation.

Mid-to-near-infrared spectral translation plays an important role in various applications in mid-infrared spectral range. However, the conversion efficiency and spectral tuning range were usually limited by the large frequency detuning between the pump and mid-infrared signal. In this work, a As2Se3 chalcogenide waveguide was proposed to fulfill phase matching condition in four-wave mixing with large pump-signal frequency detuning. The waveguide geometry was optimized through dispersion engineering to provide normal group velocity dispersion and negative fourth-order dispersion around 2 μm. The mid-to-near-infrared spectral translation with high efficiency and wide-band tunability was facilitated. By using a pump wavelength in the normal dispersion regime, the spectral translation and parametric amplification of mid-infrared signal ranging from 2.7 to 6.2 μm is obtained. The proposed waveguide has great potentials in high-sensitivity detection of mid-infrared signals and widely tunable mid-infrared generation.

A scheme based on the interaction of photon-superconducting qubit-phonon three-body hybrid quantum system is proposed, which is specifically composed of a microwave cavity and a micromechanical resonator coupled with a superconducting charge qubit. The probe absorption properties of the superconducting qubit coupled microwave cavity and mechanical resonator system are analyzed in detail through the first-order linear susceptibility which is solved by the quantum Langevin equation. The results show that the dual-field detecting method can accurately measure the coupling strength between the qubit and the microwave cavity according to the width between the double peaks in the absorption spectrum of the signal field. At the same time, according to the positions of the absorption peak and gain peak, accurate measurement of the vibration frequency is achieved. The new measurement scheme proposed in this paper is of great significance to the fields of precision measurement, quantum computing and quantum information processing.

In this paper, an open flexure hinge lever structure is combined with metallized fiber Bragg grating (FBG) to create an FBG pressure sensor for dynamic track weighing. First, metallized FBG is adopted so that it could be easily welded to the flexible hinge bracket. The FBG demodulator with a high response frequency is then used to read experimental data at rapid speed. Finally, electromagnetic interference problem in the testing system is fundamentally solved using the FBG pressure sensor, and the hinge connection is employed to replace the rigid connection to improve the sensor's sensitivity. The experimental results show that the sensor's pressure sensitivity can reach 60.8 pm/t and the strain sensitivity can reach 5.653 pm/με.

Based on the phenomenon of laser light intensity scintillation in the turbulent atmosphere, this paper builds a crosswind measurement system, proposes a maximum trend matching algorithm to match the trend sequence of the fitted laser echo signal, calculates the time delay of two echo signals, and deduces the synthetic wind speed on the entire path. The system and the standard wind measurement radar are used to simultaneously measure the target path of 117, 225, and 485 m respectively. The experimental results show that the correlation coefficients of the measurement data of two devices are 0.8567, 0.8327 and 0.7647, which are in good agreement. In addition, the system adopts a transceiver integrated configuration, compact structure, light weight, small volume, easy to carry, simple algorithm, and high measurement accuracy.

The self-assembly template method is a low-cost method suitable for making large-area nanostructures. Compared with the polystyrene microsphere template, the through-hole anodized aluminum oxide (AAO) template has the advantages of adjustable parameters, good insulation and stability, and is widely used in the preparation of many large-area patterned nanostructures which can be used to improve the performances of optoelectronic devices. In this paper, the preparation methods of AAO template are introduced firstly. Then the methods of preparing patterned nanostructures such as nanoparticles, nanowires/rods, nanotubes by AAO template are summarized. Next, the applications of the patterned nanostructures in optoelectronic devices such as solar cells, photodetectors and light-emitting diodes are introduced. Finally, the full text is summarized and the development of through-hole AAO template assisted patterning nanostructures are prospected.

Laser micro-nano connection connection technology is the basis for mass production of micro-nano structures and electronic components, and is a key technology in the field of micro-nano manufacturing. Based on a brief introduction to the application requirements and main technical methods of micro-nano connection technology, this paper focuses on the analysis and discussion of the micro-nano-scale laser connection technology. Firstly, the dimension range of laser connection technology is introduced, and then three typical laser micro-nano connection technologies are selected according to the different process characteristics, namely laser micro welding technology, micro-nano-scale laser soldering technology and laser soldering bumping technology, the research on the processing principles and characteristics, process parameters and application status of the three technology are reviewed, respectively. Through the summary of the research and application status of laser micro-nano connection technology, this paper discusses the important role of laser micro-nano connection technology in the field of aerospace, microelectronic packaging, medical device,etc., and summarizes the development direction and future research work of laser micro-nano connection technology.

To improve fiber optic communication capacity, multicore fiber, a space division multiplexing implementation option, has attracted increasing research interest. At the same time, various new active and passive optical devices based on multicore fibers are emerging. Multicore fiber grating, which can combine the unique advantages of multicore fiber and fiber grating, offers a wide range of possibilities for the design and application of new all-fiber devices in various fields, such as fiber optic communication, fiber optic sensing, and fiber lasers. In this paper, multi-core optical fiber inscription is classified as selective inscription and full-core inscription. Various multi-core fiber grating inscription schemes based on different light sources and different inscription methods are introduced. The technical characteristics of the different schemes are analysed relative to different application scenarios.