Zhang Bingjian   Wu Kan   Zhang Tianzhu  

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By controlling the wavelength and power of multiple light sources, we have realized a highly flexible Nyquist pulse generation scheme in which the pulse repetition frequency, pulse multiplication factor, waveform envelope shape and duty cycle are all tunable. By modulating the 3.2 GHz RF signal, we experimentally generated Nyquist pulses with a repetition rate of 6.4 GHz and 9.6 GHz and a rectangular wave with a duty cycle of 0.26 and a sawtooth wave with a duty cycle of 0.52.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第7期 pp.07      

Zhang Zhongkai   Lv Zunren   Yang Xiaoguang   Chai Hongyu   Meng Lei   Yang Tao  

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We report 25-Gb/s high-speed directly-modulated ground-state operation of 1.3-μm InAs/GaAs quantum dot lasers grown by molecular beam epitaxy. The active region of the lasers consists of eight layers of p-doped InAs QDs with high uniformity and density. Ridge-waveguide lasers with a 3-μm-wide and 300-μm-long cavity show a low threshold current of 14.4mA at 20℃ and high temperature stability with a high characteristic temperature of 1208K between 20℃ and 70℃. Dynamic response measurements demonstrate that the laser has a 3dB bandwidth of 7.7GHz at 20℃ and clearly-opened eye diagrams even at high temperatures up to 75℃ under a 25-Gb/s direct-modulation rate.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第7期 pp.07      

Ma Cong   Chen Hao   Ye Xingwei   Wang Xiangchuan   Pan Shilong  

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We demonstrate a microwave photonic radar with post-bandwidth synthesis, which can realize target detection with ultra-high range resolution using relatively small-bandwidth radio frequency (RF) frontends. In the proposed radar, two temporal-overlapped linear frequency-modulated (LFM) signals with the same chirp rate and different center frequencies are transmitted. By post-processing the de-chirped echos in the receiver, a signal equivalent to that de-chirped from an LFM signal with the combined bandwidth is achieved. In a proof-of-concept experiment, two LFM signals with bandwidths of 8.4 GHz are exploited to achieve radar detection with an equivalent bandwidth of 16 GHz, and a range resolution of 1 cm is obtained.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第7期 pp.07      

Chen Huanyang   Xiao Wen  

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In this letter, we find that Morse potential (proposed about 90 years ago) could be connected to Coulomb potential (or Newton potential) and harmonic potential (or Hooke potential) by conformal mappings. We thereby design a new conformal lens from Morse potential, Eaton lens and Luneburg lens and propose a series of generalized Eaton/Luneburg lenses. We find that this Morse lens is a perfect self-focusing asymmetric lens, which differs from Mikaelian lens. Our theory provides a new insight to Morse potential and other traditional potentials and revisits their classical applications on designing lenses.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Zhao Yan   Zhang Haiwei  

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In order to achieve the accurate measurement of displacement, this paper presents a self-mixing interference (SMI) displacement measurement method suitable for speckle effect. Because of the speckle effect, the amplitude of SMI signal fluctuates greatly, which will affect the measurement accuracy of displacement. EEMD is used to process SMI signal, which can filter out high-frequency noise and low-frequency noise at the same time. The envelope of SMI signal is extracted by Hilbert transform and it is used to realize the normalization of SMI signal. Through a series of signal processing, the influence of speckle on SMI signal can be effectively reduced and the SMI signal can be transformed into standard form. The displacement can be reconstructed by fringe counting and interpolation method. The experimental results show that the method is successfully applied to the displacement measurement in the presence of speckle, which verifies the effectiveness and feasibility of the method.

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

Huang Lei   Zheng Yamin   Guo Yading   Zhang Lin   Sun Chuang   Wang Xiaojun  

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A 21.2 kW, 1.94 times diffraction limited quasi-continuous wave laser is presented in this Letter based on a multi-stage, power-scalable Yb:YAG master-oscillator-power-amplifier (MOPA) system under adaptive optics (AO) control. Output laser of the MOPA system is a rectangular beam with a length-width ratio of 2:1, a 200 μs pulse duration and a 1000 Hz repetition rate. With the AO control system, the beam quality of the laser is improved from 4.20 to 1.94 times diffraction limited. To our knowledge, this is the best quality laser in the 20-kW class except for combined lasers.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Wang Shangchun   Li Zhengyong  

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We report a new method to deeply analyze the scrambling characteristic of polarization scramblers based on density of polarization states (DPS) statistics, which makes it possible to describe the DPS distribution in detail on the whole Poincaré Sphere, thus easy to locate accurately the nonuniform areas of defective polarization scramblers, which can not be realized by existing methods. We have built a polarization scrambling system to demonstrate the advantages of our method compared with others by experiments, and suggested effective evaluation indexes whose validity is well confirmed by applying to commercial scrambler. Our conclusions are valuable for accurate analyzing and diagnosing the performance of any polarization scrambler, and quality evaluation of polarization controllers or other polarization devices.

       PDF全文 (下载：4)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Khalid Ata Ur Rahman   Liu Juan   Ullah Naeem   Jia ShiQi  

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We propose and numerically demonstrate a dynamic beam deflector based on plasmonic resonators loaded thermo-responsive free-standing hydrogel which swells and collapses in water by temperature. For this purpose, we utilize four-step phase gradients mounted on free-standing hydrated hydrogel. For the normal incidence, the linearly orthogonal light deflects to 19.44° in collapsed state and 14.40° in swollen state of hydrogel. Furthermore, the light deflects at third angle i.e. 12.29° when solvent changes from water to ethanol. It is expected that our meta-design will provide a platform for dynamic holography, active lensing, data storage and, anti-counterfeiting.

       PDF全文 (下载：12)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Shao Zhengpeng   Wu Kan   Chen Jianping  

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All-optical light control plays an important role in optical signal processing and communications. In this letter, we demonstrate the all-optical inverter using the carbon nanotubes (CNT)-polyvinyl alcohol (PVA) thin film and obtain a long time stable output due to the environmental insensitivity of the device. Thermo-optic effect in the CNT-PVA thin film generates a thermal lens and modifies the beam propagation in the thin film. The obtained all-optical inverter has a front (trailing) time constant of ~ 55 μs (44 μs) for 1550 nm signal pulses and ~7 kHz response bandwidth.

       PDF全文 (下载：1)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Sutkowski Marek   Paśko Sławomir   Bakanas Ramunas  

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In the paper a method for shape visualization of small objects (microscopic) in the form of a hologram is presented. It consists of standard optical set-up for small object registration (i.e. stereoscopic or biological microscope). The Focus Stacking (FS) technique is used to obtain series of images with increased depth of field and on them a shape reconstruction procedure (Structure from Motion – SfM) is made. With use of a dense cloud of points a sequence of parallax-related images suitable for Geola’s digital holographic printing is generated. Holographic printer produces single parallax holographic (full 3D) images of real or virtual objects.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Wang Jianxin   Wang Xianghui   Zeng Ming  

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Broadband transverse displacement sensing by exploiting the interaction of a focused radially polarized (RP) beam with a silicon hollow nanodisk is proposed. The multipolar decomposition analysis indicates that the interference between a longitudinal total electric dipole (TED) moment and a lateral magnetic dipole (MD) moment is dominant in the far-field transverse scattering in the near-infrared region. Within a broadband wavelength range with the width of 155nm, the longitudinal TED is almost in phase with the lateral MD and then broadband position sensing based on the sensitivity of scattering directivity to transverse displacement can be achieved.

       PDF全文 (下载：6)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Han Yaru   Xiong Bing   Sun Changzheng   Hao Zhibiao   Wang jian   Han Yanjun   Wang Lai   Li Hongtao   Yu Jiadong   Luo Yi  

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An equivalent circuit model including multi-section distributed parameters is proposed to analyze wideband photodiodes (PDs) with coplanar waveguide (CPW) electrodes. The model helps extract CPW parameters as well as intrinsic bandwidth parameters, so that the influence of CPW structure can be investigated, making it valuable for the design of high performance PDs. PDs with an inductive 115-Ω impedance CPW are fabricated, and the 3-dB bandwidth is improved from 28 GHz to 37.5 GHz, compared with PDs with conventional 50-Ω impedance CPW.

       PDF全文 (下载：3)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Chen Zhengxi   Huang Zhitong   Ji Yuefeng  

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This letter proposes a model of indoor VLC heterogeneous networks entirely based on LEDs with different specifications and applies non-orthogonal multiple access (NOMA) to it because of the narrow modulation bandwidth of LEDs. Moreover, a user-grouping scheme which is based on matching theory is proposed to improve the network achievable sum rate. Simulation results indicate that when each NOMA cluster contains 6 users, the proposed scheme has 49.54% sum-rate enhancement compared with the traditional user-grouping scheme. As the number of users in each NOMA cluster increases, the proposed scheme performs better at the cost of computational complexity.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Zhang Zongyi   Wu Yonggang   Xia Zihuan   Zhou Jian   Qin Xuefei  

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Rotating elliptical nanowire arrays as the two-dimensional photonic crystals has been proposed and studied in this letter. The analysis of the four lowest energy band and first band gap width of some examples illustrates that the rotation and configuration of the primitive cell can have effects on the reducibility of Brillouin zone. As the central element’s orientation changes, the irreducible Brillouin zone could be expanded to the whole first Brillouin zone. Special attention has been paid to the nanowire arrays with adjacent elements perpendicular to each other, and the irreducible Brillouin zone unexpectedly retracted back to the 1/8 of the first Brillouin zone though the symmetry of elements is lower than that of the square lattice. Meanwhile, the first band gap width of the perpendicular array can be adjusted by the rotation of each primitive element.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Liu Gonghai   Zhao Gongyuan   zhang Gong   lu qiaoyin   guo weihua  

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We experimentally demonstrated that the DFB lasers with active distributed reflector achieved a 25.8 Gb/s operation over wide temperature range of -40 – 85 ºC. The DFB lasers can achieve additional feedback from active distributed reflector with accurately controlled phase, and single mode yield are not related to the position of cleave. The threshold current of the fabricated laser are 6 mA and 20 mA at -40 ºC and 85 ºC, respectively. The side mode suppression ratio of the fabricated laser is above 50 dB at all temperature. 25.8 Gb/s transmissions after 10-km single-mode fibers with clear eye openings and less-than 0.8 dB power penalty over a wide temperature range have been demonstrated as well.

       PDF全文 (下载：6)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Chen Hualong   jiang xiantao   Xu Shixiang   Zhang Han  

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In recent years, multi-wavelength fiber lasers play a significant role in plenty of fields, ranging from optical communications to mechanical processing and laser biomedicine owning to their high beam quality, low cost and excellent heat dissipation properties. Benefitting from increasing maturity of optical elements, multi-wavelength fiber laser has got rapid developments. In this review, we summarize and analyze diverse implementation methods covering continuous wave (CW) and pulsed fiber laser at room temperature condition: inserting optical filter device and intensity-dependent loss structure in the resonant cavity, applying ultrafast nonlinear optical response of materials and dual-cavity structure. Finally, future challenges and perspectives of multi-wavelength fiber laser are discussed and addressed.

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

rong wang   Fang Zhiheng   hai an   Xiong Jun   yong xie   Guo Erfu   Wang Chen   Lei Anle   Wang Wei  

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An aberration-free imaging technique was used to design a double-spherically bent crystal spectrometer with high energy and spatial resolution to ensure that the individual spectral lines are represented as perfectly straight lines on the detector. After obtaining the matched parameters of the two crystals via geometry-based optimization, an alignment method was employed to allow the spacing between the crystals and the detector to be coupled with the source. The working principle of this spectrum-measuring scheme was evaluated using a Cu X-ray tube. High-quality spectra with energy resolution (E/ΔE) of approximately 3577 were obtained for a relatively large source size.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

qishu Qian   Yihua Hu   Nanxiang Zhao   Minle Li   Fucai Shao   Xinyuan Zhang  

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To fully describe the structure information of the point cloud when the LIDAR-object distance is far, a joint global and local feature (JGLF) descriptor is constructed. Compared with five typical descriptors, the object recognition rate of JGLF is higher when the LIDAR-object distances change. Under the situation that airborne LIDAR is getting close to the object, particle filtering (PF) algorithm is used as the tracking frame. And particle weight is updated by comparing the difference between JGLFs to track the object. It is verified that the proposed algorithm performs 13.95% more accurate and stable than that of the basic PF algorithm.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

BAO Haihong   Jin Wei   Ho Hoilut  

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We report the first demonstration of group delay tuning with stimulated Raman scattering induced dispersion in a hydrogen-filled hollow-core optical fiber. A pump laser induces sharp refractive index change near the S0(0) Raman transition of hydrogen molecules, enabling the control of the group velocity of signal pulses around the Stokes wavelength. Experiment with an 80-m-long hollow-core fiber filled with 2.5-bar hydrogen achieved continuously tuning of pulse delay up to 1.42 ns by varying the Raman gain from 0-10 dB. Tunable pulse delay is realized by changing pump power as well as hydrogen pressure. This work provides a new technique for controlling pulse propagation in optical fibers with high flexibility.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

Shang Hongbo   Zhang Luwei   Liu Chunlai   Wang Ping   Sui Yongxin   Yang Huaijiang  

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Polarization aberration caused by material birefringence can be partially compensated by lens clocking. In this paper, we propose a fast and efficient clocking optimization method. Firstly, the material birefringence distribution is fitted by the orientation Zernike polynomials. On this basis, the birefringence sensitivity matrix of each lens element can be calculated. Then we derive the rotation matrix of the orientation Zernike polynomials and establish the mathematical model for clocking optimization. Finally, an optimization example is given to illustrate the efficiency of the new method. The result shows that the maximum RMS of retardation is reduced by 64% using only 48.99s.

       PDF全文 (下载：2)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

singh Leena   Zhang Weili  

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Refractive index enhancement is crucial in the field of lithography, imaging, optical communications, solar devices and many more. We present a review of advancements in the process of designing high refractive index metamaterials, starting from quantum coupling and photonic bandgap materials to metamaterials utilizing deep subwavelength coupling to achieve ever-high values of refractive index. A particular interest is given to experimentally verified schemes in engineering high index of refraction. The Understanding of evolution of material design from intrinsic electronic states manipulation to meta-atoms design is not only fascinating but prerequisite to developing successful devices and applications.

       PDF全文 (下载：0)        Chinese Optics Letters ，2020年第18卷第6期 pp.06      

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：22)        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：9)        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：5)        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：3)        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：10)        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：9)        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：14)        Chinese Optics Letters ，2020年第18卷第5期 pp.05