Lin Tianying   Ze Chen   Xiaopei Zhang   Li He   Xiaoping Liu   Haibin Lv  

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Photonic waveguide arrays provide a simple and versatile platform for simulating conventional topological systems. Here we investigate a novel one-dimensional (1D) topological band structure, a dimer chain, consisting of silicon waveguides with alternating self-coupling and inter-coupling. Coupled mode theory is used to study topological features of such model. It is found that topological invariants of our proposed model are described by the global Berry phase instead of the Berry phase of the upper or lower energy band, which is commonly used in the 1D topological models such as SSH model. Next, we design an array configuration composed of two dimer patterns with different global Berry phases to realize the topologically protected waveguiding. The topologically protected propagation feature is simulated based on Finite-Difference Time-Domain (FDTD) method and then observed in the experiment. Our results provide an in-depth understanding of the dynamics of the topological defect state in a 1D silicon waveguide array, and may provide different routes for on-chip lightwave shaping and routing.

       PDF全文 (下载：9)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Li Hongye   Liang Hu   Hu Qihao   Wang Meng   Wang Zefeng  

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We propose here a novel method for position fixing in micron-scale by combining the convolutional neural networks (CNN) architecture and speckle patterns generated in a multimode fiber. By varying the splice offset between a single mode fiber and a multimode fiber, speckles with different patterns can be generated at the output of the multimode fiber. The CNN is utilized to learn these specklegrams and then predict the offset coordinate. Simulation results show that predicted positions with the precision of 2 μm account for 98.55%. This work provides a potential high-precision two-dimensional positioning method.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Ma xiaorong   Chen Hong   Hou Junwei   jia zhenhong   Wu Guohua   lv xiaoyi   Li Hongyi   Zheng Xiangxiang   chen chen  

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In this paper, the surface-enhanced Raman scattering (SERS)signal of BRC patient serum obtained by a porous silicon (PSi) Bragg reflector with silve nanoparticles(Ag NPs). Based on these advantages, the serum SERS of 30 normal people and 30 BRC patients were detected by this substrate. After abaseline correction of the experimental data, principal component analysis and linear discriminant analysis (PCA-LDA) were used to complete the data processing. The results showed that the diagnostic accuracy, specificity and sensitivity of the PSi Bragg reflector SERS substrate with composite Ag NPs were 95%, 96.7%, and 93.3%respectively. The results of this exploratory study prove that the detection of BRC serum based on the composite Ag NPs PSi Bragg reflector SERS substrate is a stable, strong SERS signal, unmarked and noninvasive BRC diagnosis technology. In the future, this technology can serve as anoninvasiveclinical tool to detect cancer diseases and have a consider able impact on clinical medical detection.

       PDF全文 (下载：4)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Wang Wu   Xinbing Wang   Duluo Zuo   Zakharov Vassily  

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Laser induced discharge plasma (LDP) can be used as inspection and metrology EUV sources for its simplicity. To avoid the tin electrode erosion, a LDP EUV source, in which a tin pool was used as cathode, was developed. A CO2 pulse laser was focused on the liquid tin target surface, and then a breakdown occurred in a very short time. The voltage-current characteristics of the discharge oscillated, and lasted for several microseconds, and a RLC fitting model was used to obtain the inductance and resistance. An ICCD camera was used to investigate the dynamic of LDP, which can explain the formation of a discharge channel. The EUV spectra of laser induced liquid tin discharge plasma were detected by a grazing incident ultraviolet spectrometer, compared with laser produced tin droplet plasma EUV spectrum. To explain the EUV spectra difference of laser induced liquid tin discharge plasma and laser produced tin droplet plasma, the collision radiation (CR) model combined with COWAN code was used to fit the experimental EUV spectrum, which can estimate the electron temperature and density of the plasma.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Ji Encai   Shi Jie   Zha Congwen   Zeng Jing   Zhou Xinwu   He Zhengdi   Yao Yong   Lue Qitao  

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The ultimate capacity of cladding-pumped 10/130 Tm: fiber is experimentally investigated with a 793nm LD bidirectionally pumped amplifier. The laser system works stably at the output power of 52W, 65W, and 87W. Eventually, the damage of the amplifier occurs when the output power reaches about 103.5 W with a total incident pump power of 176.8W. Considering the incident seed power of 12.3W, the amplifier conversion efficiency is estimated about 51.6% before it is damaged. With the valuable exploration, we achieve the first air-cooling 60 W Tm: fiber laser at 1945.845 nm with a spectra linewidth of 0.4 nm. The laser power stability reaches 1.24% during a continuous test time of >65 hours. The beam quality is measured as Mx2=1.16, My2=1.14.

       PDF全文 (下载：6)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Yang Yuting   Zhao Gang   Huang Yue   Feng Wen   Huang Lin   Liu Xin  

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A high repetition rate, picosecond THz parametric amplifier (TPA) with a LiNbO3 (LN) crystal has been demonstrated in this work. At 10 kHz repetition rate, a peak power of 200 W and an average power of 12 μW have been obtained over a wide range around 2 THz; at 100 kHz repetition rate, a maximum peak power of 18 W and average power of 10.8 μW have been obtained. The parametric gain of the LN crystal was also investigated and a modified Schwarz-Maier model was introduced to interpret the experimental results.

       PDF全文 (下载：6)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Li Xiaoman   Zhou Shaoshuai   Wei Rongfei   Liu Xueyun   Cao Bingqiang   Guo Hai  

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To introduce ordered nano-structure inside transparent amorphous matrix with superior optical and mechanical properties bears scientific and technological importance, yet limited success has been achieved. Here, via simple melting-quenching and subsequent thermal activation, we report the successful preparation of a transparent nano-structured glass ceramics embedded with Sr₂LuF₇ nano-crystals (~26 nm), as evidenced by XRD, TEM and HRTEM. The successful incorporation of dopants into formed Sr₂LuF₇ nano-crystals with low phonon energy results in highly tunable blue-green photo-emission, which depending on excitation wavelength, dopant type and temperature. We found that Eu³⁺ and Eu²⁺ ions co-exist in this hybrid optical materials, accompanied by the broadband blue emission of Eu²⁺ and sharp red emissions of Eu³⁺. Series of optical characterizations are summoned, including emission, excitation spectra and decay curve measurement, to reveal the reduction mechanism of Eu³⁺ to Eu²⁺. Furthermore, near green-white photo-emission is achieved via the enrichment of Tb³⁺/Eu³⁺ into crystallized Sr₂LuF₇ nano-crystals. The temperature-dependent visible photo-emission reveals thermal activation energy increases with the precipitation of Sr₂LuF₇ nano-crystals in glass matrix, suggesting better thermal stability of glass-ceramics than precursor glasses. These results could not only deepen the understanding of glass-ceramics but also indicate the promising potential of Eu³⁺/Tb³⁺ ions doped-Sr₂LuF₇ glass-ceramics for UV pumped WLEDs with good thermal stability.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Tian Rong   Li Yi   Liu Zhimin   Zhou Jianzhong   Liu Jin   Fan Lina   Zhao Wenqing   Li Junxian   Zhang Xin   Peng Chuang   Wu Yuda   Wang Xiaohua   Fang Baoying  

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In this paper, we propose a broadband NIR absorber based on the phase transition material VO2. By designing different arrangements of the VO2 square lattice at high and low temperatures on fused silica substrates, the absorption rate reaches more than 90% in the entire 1.4-2.4 μm range. Using a finite-difference time-domain simulation method and thermal field analysis, the results prove that the absorber is polarization-independent and has wide-angle absorption for incident angles of 0°-70°. The proposed absorber has a smoother absorption curve and is superior in performance, and it has many application prospects in remote sensing geology.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Wang Bochen   Li Zhengyong  

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We propose and demonstrate a novel scheme of the semi-open-loop polarization control (SOL-PC), which controls the state of polarization (SOP) with high accuracy and uniform high speed. For any desired SOP, we firstly adjust the initial SOP by the open-loop control (OLC) based on the matrix model of a three-unit piezoelectric polarization controller, and quickly move it close to the objective one. Then the close-loop control (CLC) will be performed to reduce the error and reach precisely the desired SOP. The response time is three-order faster than that of the present close-loop polarization control, while the average deviation is on a par with it. Finally the SOL-PC system is successfully applied to realize the suppression of polarization mode dispersion (PMD) effect, and reduce the first-order PMD to near zero. Due to its perfect performance, the SOL-PC will energize the present polarization control to pursue an ideal product, which can meet the future requirements in ultrafast optical transmission and quantum communication.

       PDF全文 (下载：8)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Li Simin   Cong Rong   He Zhengqian   Wang Tianliang   Zhang Fangzheng   Pan Shilong  

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A switchable microwave photonic filter (MPF) using a phase modulator (PM) and a silicon-on-insulator (SOI) micro-ring resonator (MRR) is proposed and demonstrated. By adjusting the polarization controller (PC) between the PM and the MRR, the filtering function of the MPF can be switched between a band-stop filter and a band-pass filter. In a proof-of-concept experiment, an MPF with a rejection ratio of 30 (or 15 dB) for the band-stop (or band-pass) response and a frequency tuning range from 9.6 to 27.6 GHz is achieved.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Zhu Gaoyan   Xiao Lei   Huo Bingzi   Xue Peng  

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Quantum walks, a counterpart of classical random walks, have many applications due to its neoteric features. Since was firstly proposed, quantum walks have been explored in many fields theoretically and also been demonstrated experimentally in various physical systems. In this article, we review the experimental realizations of discrete-time quantum walks in photonic systems with different physical structures, such as bulk optics and time-multiplexed framework. And then some typical applications using quantum walks are introduced. Finally, the advantages and disadvantages of these physical systems are discussed.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Ye Zhicheng   Zheng Jun  

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A grating-coupled surface plasmon resonance sensor based on bilayer aluminum nanowire arrays is fabricated by laser interfere lithography. The device presents impressive reflective sharp peaks by lateral surface plasmon resonances even for aluminum thickness merely of several nanometers. Distinct reflective peaks and dramatic color shifts under different analytes are observed within a wide range of incident angle, metal thickness, and refractive index. The sensitivity of 307 nm per refractive index unit is experimentally obtained. The reflective-peak-typed surface plasmon resonance sensors are suitable for practical applications, because of easy fabrication, low cost wide range, and high signal visibility.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Zheng Ming   Yu Qingnan   Tai Hanxu   Zhang Jianwei   Ning Yongqiang   Wu Jian  

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The unamplified spontaneous emission（SE）is one of important physical processes of the light-matter interaction in a diode laser, in terms of Einstein’s theory. The recent research on a kind of new indium-rich cluster (IRC) laser structure did not reveal SE characteristics of the IRC structure, as its unusual quantum confined structure made it difficult to acquire correctly the SE spectra through theoretical simulation or previous experimental techniques. Thus, in this paper we firstly established a convenient and effective experimental approach to acquire SE spectra of the IRC structure by the measurement of amplified spontaneous emissions from dual facets of a single edge-emitting chip with little sample processing. With the proposed method, the special SE spectra due to the IRC effect were observed. Then, the SE formation mechanism and characteristics in the IRC structure were analyzed by comparing the experimental data with theoretical SE spectra using a standard InGaAs/GaAs quantum well with the similar material composition. This research provides a useful tool to investigate the SE characteristics of any non-standard diode laser structure and is very meaningful to developing a new type of IRC lasers.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Shen Chencheng   Cai Xianglong   Sang Youbao   Zheng Tiancheng   Li Zhonghui   Liu Dong   Liu Wanfa   Guo Jingwei  

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In this work, SF6 as Raman-active medium is investigated to generate multispectral Raman laser by the combination of cascade stimulated Raman scattering and four wave mixing. The Raman frequency comb from the 10th order anti-Stokes to the 9th order Stokes was generated, and its spectral range covered 377-846 nm. The photon conversion efficiency of 16.4% for the first Stokes was achieved, and the Raman gain coefficient at 1.5 MPa of SF6 under the 532 nm pump laser was calculated to be 0.83 cm/GW by the SRS threshold comparison with H2. Using helium as carrier gas, the thermal effect of SF6 Raman laser was improved dramatically under repetition rate of 10 Hz.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Yang Kangwen   Li Hai   Gong Hang   Hao Qiang   Huang Kun   Shen Xuling   Yan Ming   Zeng Heping  

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We demonstrated absorption spectroscopy on water vapor for the determination of gas temperature. An adaptive dual-comb detection system is utilized to obtain precise spectroscopic data in a broadband range from 7143 to 7240 cm-1 with a spectral resolution of 0.049 cm-1. The measured spectra are in accordance with the simulated results from HITRAN database. Several measurements are investigated in the temperature range of 500-1000 K, revealing relative deviations of less than 5% compared to the thermocouple. This broadband and accurate adaptive dual-comb spectral detection method could be a powerful tool for non-invasive combustion diagnosis.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第5期 pp.05      

Guan Xianghe   Zhang Junyong   zhang yanli   Zhu Jianqiang  

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Laguerre-Gaussian (LG) mode beam has very important applications in many research fields. Here, Theon sieve is first introduced into the laser resonator and to generate petal-like laser beam by coherently superimposing two high-order LG mode. The effectiveness was verified by GLAD software. The petal-like laser beam is derived from the light field redistribution and coherently superposition caused by the diffraction effect of Theon sieve. The relationship between the order of petal-like laser and the cavity structures has also been investigated in detail. Light field operation in laser cavity greatly simplifies the optical structure and is more beneficial to optical diagnostics and imaging.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Wang Xin   Liu Honglin   Chen Meijun   Liu Zhentao   Han Shensheng  

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Imaging through scattering media via speckle autocorrelation is a popular method based on the optical memory effect. However, it fails if valid information acquired is insufficient due to a limited sensor size. In this paper, we reveal a relationship between detector and object sizes for the minimum requirement to ensure image reconstruction by defining a sampling ratio R, and propose a method to enhance image quality at a small R by capturing multiple frames of speckle patterns and piecing them together. This method will be helpful in expanding applications of speckle autocorrelation to remote sensing, underwater probing and so on.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Yu Lei   Zou Weiwen   Li Xinwan   Chen Jianping  

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We demonstrate a novel multi-functional radar receiver scheme based on the photonic parametric sampling. The working principle of the photonic parametric sampling based on four wave mixing (FWM) process is presented. To experimentally verify the multi-functional feasibility, the scheme is individually implemented to carry out a four-channel phased array radar reception and a dual-band radar reception.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Tang Tianhong   Zhang Fang   Wang Mengxia   Wang Zhengping   Xu Xinguang  

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For the first time, a group-VI single element nanomaterial was used as the optical saturable absorber (SA) to genetate laser pulses. With two-dimensional (2D) tellurene as passively Q-switcher, the 1.06 and 1.3 µm pulse laser operations were realized from a diode-pumped Nd:YAG crystal. The shortest pulse widths were 98 ns, 178 ns, and the highest peak powers were 2.68 W, 2.45 W, respectively. Our research manifests that tellurene is an excellent SA material in near infrared region.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Kim Sung-Man   Park Hanbit  

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We experimentally demonstrated optical wireless power transfer (OWPT) using a near-infrared laser diode (LD) as the optical power transmitter. We considered a photovoltaic (PV) cell and a photodiode (PD) as the optical power receivers. We investigated the characteristics of the LD, PD, and PV cell in order to determine the optimum operating condition from the viewpoint of transfer efficiency. We also experimentally demonstrated a whole system optimization process to maximize the DC-to-DC transfer efficiency of the OWPT. Our experimental results showed that the optimization process can improve the OWPT efficiency by upto 48 %.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Liu Huiyuan   Wen He   Li Guifang  

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Space-division multiplexing (SDM) has attracted significant attention in recent years, because larger transmission capacity is enabled by more degrees of freedom (DOFs) in few mode fibers (FMFs) compared with single mode fibers (SMFs). To transmit independent information on spatial modes without or with minor digital signal processing (DSP), weakly-coupled FMFs are preferred in various applications. Several cases with different use of spatial DOFs in weakly-coupled FMFs are demonstrated in this work, including single-mode or mode-group-multiplexed transmission, and spatial DOFs combined with time or frequency DOF to improve the system performance.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Liu Renqi   peng chun   Liang Xiaoyan   Li Ruxin  

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A deep convolutional neural network is employed to simultaneously measure the beam-pointing and phase difference of sub-beams from a single far-field interference fringe for the coherent beam combining systems. Especially, the amplitudes of sub-beams in measurement path are modulated in order to prevent measuring mistake caused by symmetry of beam-pointing. This method is able to measure beam-pointing and phase difference with an RMS accuracy of about 0.2μrad and λ/250 respectively in a two-beam coherent beam combining system.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Xiaodong Mei   Wang Chenglong   Fang Yami   Song Ting   Gong Wenlin   Han Shensheng  

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We investigate the influence of the source's energy fluctuation on both computational ghost imaging and computational ghost imaging via sparsity constraint, the reconstruction quality will decrease with the increase of the source's energy fluctuation. In order to overcome the problem of image degradation, a correction approach against the source's energy fluctuation is proposed by recording the source's fluctuation with a monitor before modulation and correcting echo signal or the intensity of computed reference light field with the data recorded by the monitor. Both numerical simulation and experimental results demonstrate that computational ghost imaging via sparsity constraint can be enhanced by correcting echo signal or the intensity of computed reference light field, while only correcting echo signal is valid for computational ghost imaging.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Bai Bing   Pei Li   Zheng Jingjing   Ning Tigang   Li Jing  

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We propose and analyze a silicon hybrid plasmonic polarization splitter-rotator with ultra-short footprint using asymmetric bent directional coupler on silicon-on-insulator platform. Benefiting from the large birefringence induce by bent structure and plasmonic effect, the cross-polarization coupling length is only 5.21 μm. The transverse magnetic to transverse electric polarization conversion efficiency is over 99.9% with extinction ratio of 20.6 dB (32.5 dB) for transverse magnetic (transverse electric) mode at 1.55 μm. Furthermore, the polarization conversion efficiency is higher than 90% while maintaining crosstalk below -19 dB within the bandwidth of 80 nm.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Wang Guanxue   Li Yue   Miao Yu   Shan Xinzhi   Gao Xiumin  

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In this paper, vortex phase and sinusoidal phase modulation of Hermite-Gaussian beams are studied theoretically and experimentally. The coding method of experiment is introduced in detail and the evolution law of focus under different beam order (m, n) and topological charge (l) is given. In order to verify the accuracy of generation experiment, the optical field distribution under sinusoidal vortex modulation is analyzed deeply. The relevant analysis and methods provided in this paper have certain practical significance for the development of laser mode analysis, optical communication and other fields.

       PDF全文 (下载：4)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

zhao mengfei   zhang zhongmian   feng xiaoyue   zong mengyu   Liu Jie   Xu Xiaodong   Zhang Han  

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A new disordered crystal Nd:SrAl₁₂O₁₉ (Nd:SRA) with an Nd³⁺ doping concentration of 5% was successfully grown using the Czochralski method. A diode-pumped Nd:SRA Q-switched laser operating at 1049 nm was demonstrated for the first time. Based on a MXene Ti₃C₂T_x sheet, a high repetition rate of 201 kHz with a Q-switched pulse width of 346 ns was obtained when the absorbed pump power was 2.8 W. The peak power and single pulse energy were 1.87 W and 0.65 μJ, respectively.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Xu Xiaofang   Li Jingbo   Yang Xiaohan   Pan Sen   Bi Yong  

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The photoelectric properties of conductive films are improved by doping silver on aluminum-doped zinc oxide (AZO) films by picosecond laser induced forward transfer (LIFT) technology. Firstly, the temperature variation of the electron and lattice in silver films under picosecond laser was numerically calculated by finite element analysis, and the relationship between picosecond laser induced transfer mechanism and film thickness was revealed：As the film thickness increases, the film is transferred from the entire area to the upper film breaking through the underlying film and forming a jet to transfer; Then, different thickness silver films were deposited on the AZO films by picosecond LIFT. We have successfully obtained some AZO films with higher optoelectronic properties under the conditions of thinner silver film and lower laser energy density; under the thick silver film (>100 nm) or the too high laser energy, the AZO films were damaged, but at this time, silver deposits on the surface of the AZO films to produce a special nanostructure.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Zhou Xue   Yuan Jie   Wang Xueding   Cheng Qian  

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The diagnosis of osteoporosis is eventually converted to the measurement of bone mineral density (BMD) in clinical try. Since our previous work had proved the abilities of using photoacoustic spectral analysis (PASA) to efficiently detect osteoporosis, in this contribution, we proposed a fully connected multi-layer deep neural network combined with PASA to semi-quantify BMD values corresponding to varying degrees of bone loss and to further evaluate the degree of osteoporosis. Experiments were carried on swine femur heads and the performance of our proposed method is satisfying for future clinical screening.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

Zhao Mantong   Zhang Dawei   Zheng Lulu   Condliffe Otto   Kang Yi  

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This study provides a rapid method for the quantification of mineral oil in rapeseed oil using near-infrared spectroscopy. The data were processed by direct orthogonal signal correction (DOSC), successive projections algorithm (SPA), partial least squares (PLS) and principle component regression (PCR). DOSC-SPA-PCR model was identified as optimal method, resulting in good correlation coefficients (R) of 0.998, root-mean-squared error (RMSE) of 0.005. A satisfactory accuracy with R and RMSE of prediction by DOSC-SPA-PCR model of 0.990, 0.006, was obtained. The results demonstrate that the proposed methodology is a promising method for the rapid quantitative detection of mineral oil in vegetable oil.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第4期 pp.04      

chen jiannong   Wang Baodong   Zhu Linwei   Han Jing   xu qinfeng  

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We propose a metalens for coaxial double wavelength focusing. One focusing spot is circular solid spot and another focusing spot is a doughnut-shaped spot which is circling the solid spot. The designed metalens was composed of meta-molecular nanostructured cell array. Each meta-molecular nanostructured cell was divided into four squares. Two slots with exactly the same shape but usually with rotation angle measured clockwise from positive x axis are etched into the gold film in diagonally connected two squares. Another two slots with the same shape but with the rotation angle measured counter-clockwise from positive x axis are etched into another two diagonally connected squares in the same cell. The lasers with two different wavelengths are transformed into right-handed and left-handed circularly polarized beam, respectively. The two sets of slots with different azimuthal rotation modulated the phases of incident right-handed and left-handed circularly polarized beam independently. The numerical simulation with FDTD software was carried out and the experimental verification was also implemented. Both of the experimental result and the numerical simulation agree well with the theoretical design.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第4期 pp.04