Zhang Yinlong   Liang YiZhi   Jin Long   Guan Bai-Ou  

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All-optical ultrasound probe, which contains a photoacoustically based ultrasound generator paired with a photonic acoustic sensor, provide promising imaging modality for diagnostic and MRI compatible applications. Here, we demonstrate the fabrication of a fiber-based all-optical ultrasound probe and its application in pulse-echo ultrasound imaging. The ultrasound generator is fabricated on a 125-μm multimode optical fiber by forming a light-absorbing multiwalled carbon nanotubes (MWCNTs)-polydimethylsiloxane (PDMS) composite coating on its distal end. A peak-to-peak acoustic pressure 0.95 MPa has been achieved at nearly the damage threshold 2.46 μJ, by chemically functionalizing the fiber surface to enable strong nanotube adsorption. Ultrasound reception was performed by a fiber-laser ultrasound sensor which translates ultrasound pressure into differential lasing-frequency changes. By linearly scanning the probe, ex vivo two- and three-dimensional imaging of a segment of swine trachea has been demonstrated, by detecting the echo ultrasound signals and reconstructing the acoustic scatters. The probe presents axial and lateral resolutions at 150 and 62 μm, respectively. The small-sized, side-looking all-fiber ultrasound probe presents a promising approach for assembling an interventional endoscopy.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Huang Junchao   Wang Lingke   Duan Yifei   Huang Yafeng   ye meifeng   Liu Liang   Li Tang  

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We demonstrate frequency stabilization of a 1.55 μm erbium-doped fiber laser by locking it to a 5-km-long optical fiber delay line (FDL). The stabilized laser is characterized via comparison with a second identical laser system. We obtain fractional frequency stability of better than 3*10-15 over timescales of 1–10 s and a laser linewidth of 0.2 Hz, which is the narrowest linewidth of an FDL-stabilized laser observed to date.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

huang wei   cui yulong   Li zhixian   zhou zhiyue   Wang Zefeng  

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We reported here a single-pass 1.56 μm fiber gas Raman laser in a deuterium-filled hollow-core fiber and a 2.86 μm cascade fiber gas Raman laser with methane in the second stage. The maximum output power of 1.56 μm and 2.86 μm is 27 mW and 8.5 mW with Raman conversion efficiency of 30% and 42% respectively. The results offer a new method to produce 1.5 μm fiber source and prove the potential of the cascade fiber gas Raman laser in extending the available wavelength.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Zhang Min   Xu Bo   Li Xiaoyun   Cai Yi   Wu Baojian   Qiu Kun  

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A novel predictive dynamic bandwidth allocation (DBA) method based on Long Short-Term Memory (LSTM) neural network is proposed for 10-Gigabit-capable passive optical network in mobile front-haul (MFH) links. By predicting the number of packets that arrive at the optical network unit buffer based on LSTM, the round-trip time delay in traditional DBAs can be eliminated to meet the strict latency requirement for MFH links. Our study shows that LSTM has better performance than feed-forward neural network. Based on extensive simulations, the proposed scheme is found to be able to achieve the latency requirement for MFH and outperforms the traditional DBAs in terms of delay, jitter and packet loss ratio.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Lu Chenghao   Zhu Bing   Zhu Chuanyi   Ge Licheng   Liu Yi'an   Chen Yuping   Chen Xianfeng  

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All-optical logic gates including AND, XOR, and NOT gates, as well as a half-adder, are realized based on two-dimensional lithium niobate photonic crystal (PhC) circuits with PhC micro-cavities. The proposed all-optical devices have an extinction ratio as high as 23 dB due to the effective all-optical switch function induced by two-missing-hole micro-cavities. These proposed devices can have potential implementation of complex integrated optical functionalities including all-optical computing in lithium niobate slab or thin film.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Wang Aimin   Yang Wan   Wu Danlei   Wu Runlong   Liu Guanyu   Chen Bingying   Feng Lishuang   Zhang Zhigang  

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We present a Er:fiber based femtosecond laser at 780 nm with 256-MHz repetition rate, 191-fs pulse duration, and over 1-W average power. Apart from the careful third-order dispersion management, we introduce moderate self-phase modulation to broaden the output spectrum of the Er:fiber amplifier and achieve 193-fs pulse duration and 2.43-W average power. Over 40% frequency doubling efficiency was obtained by a periodically poled lithium niobate crystal. Delivering through a hollow-core photonics bandgap fiber, this robust laser becomes an ideal and convenient light source for two-photon autofluorescence imaging.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Zhang Pan   Liu Dean   Yang Aihua   Zhu Jianqiang  

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A method is proposed to optimize the recording structure of the photorefractive volume grating to compensate the high spatial frequency in the distorted wavefront by optical phase conjugation. Based on coupled-wave equation, the diffraction efficiency of the recorded grating formed by the scattered beams in different recording structures is simulated. The theoretical results show that the recorded modulations with high spatial frequency can be significantly improved in the small recording angle. In experiment, three recording structures with the recording angle 7.5°, 30° and 45° are chosen to verify the compensation effect. Compared with the reconstructed image in the large recording angle 45°, the signal to noise ratio of image recorded in 7.5° increases to 3.2 times.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Sun Xiaocong   Wang Yajun   Tian Long   Zheng Yaohui   Peng Kunchi  

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Squeezed states belong to the most prominent nonclassical resources. They have compelling applications in precise measurement, quantum computation and detection. Here, we report on the direct measurement of 13.8 dB squeezed vacuum states by improving the interference eciency and gain of balanced homodyne detection. By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%. The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction eld-eect transistor (JFET) buering input and another JFET bootstrap structure in the balanced homodyne detector.

       PDF全文 (下载：14)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Miao Runlin   Tong Mingyu   Yin Ke   Ouyang Hao   Wang Zhenyu   Zheng Xin   Cheng Xiangai   Jiang Tian  

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In this work, a soliton mode-locked erbium-doped fiber laser (EDFL) with a high-quality molecular beam epitaxy (MBE) grown topological insulator (TI) Bi2Se3 saturable absorber (SA) is reported. To fabricate the SA device, a 16-layer Bi2Se3 film was grown successfully on a 100 μm thick SiO2 substrate and sandwiched directly between two fiber ferrules. The TI-SA had a saturable absorption of 1.12 % and a saturable influence of 160 MW/cm2. After inserting the TI-SA into the unidirectional ring-cavity EDFL, self-starting mode-locked soliton pulse trains were obtained at a fundamental repetition rate of 19.352 MHz. The output central wavelength/pulse energy/pulse duration/signal to noise ratio (SNR) of radio frequency spectrum were 1530 nm/18.5 pJ/1.08 ps/60 dBm, respectively. These results demonstrate that MBE technique could provide a controllable and repeatable method for the fabrication of identical high-quality TI-SAs, which is critical important for ultrafast pulse generation.

       PDF全文 (下载：10)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Wang Yan   Lin Nan   Gao Wanli   Song Huanyu   Hu Minglie   Li Haiming   Bao Wenxai   Ma Xiaoyu   Zhang Zhigang  

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We demonstrate a strain compensated long lifetime SESAM with a high modulation depth for fiber lasers. The SESAM was measured to have a damage threshold of 9.5 mJ/cm², a modulation depth of 11.5%, a saturation fluence of 39.3 µJ/cm², and an inversed saturable absorption coefficient of 630 mJ/cm². The SESAM has been applied to a linear cavity mode-locked Yb:fiber laser, which has been working for more than a year without damage of the SESAM.

       PDF全文 (下载：7)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Sun ShengZhi   Ye Song   Wang Zhenyan   Song Juan   Qian Bin   Qiu Jianrong  

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We report on the elemental redistribution behavior in oxyfluoride glasses with a high repetition rate near-infrared femtosecond laser. Elemental analysis by Electro-Probe Microanalyzer demonstrates that the redistributions of Ca2+ and Yb3+ ions change dramatically with pulse energy, which are quite different compared with previous reported results. Confocal fluorescence spectra of Yb3+ ions demonstrate that the luminescence intensity changes obviously with the elemental redistribution. The mechanism of the observed phenomenon is discussed. This observation may have potential applications in the fabrication of micro-optical devices.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Xu Aopeng   Kong Delong   Fu Zhijie   Wang Zhaoying   Lin Qiang  

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For most of atom interferometers, vibration isolation unit is applied to reduce vibration noise. In our experiment, instead of isolation, the vibration signals are monitored, combining with the sensitive function, the compensation phase shift for the atom interferometer is obtained. We focused on the correction over a wide spectrum rather than on “monochromatic” frequencies. The sensitivity of the atom gravimeter can be upgraded by a factor of more than two. Furthermore, we demonstrated that the atom interferometer can still produce a good measurement result without passive vibration isolation in extremely noisy environments by using vibration compensation.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Li Jian   Xu Yang   Zhang Mingjiang   Zhang Jianzhong   Qiao Lijun   Wang Tao  

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We propose and experimentally demonstrate a novel Raman-based distributed fiber-optics temperature sensor for improving the temperature measurement accuracy and engineering applicability. The proposed method is based on the double-ended demodulation with a reference temperature and dynamic dispersion difference compensation method, which can suppress the effect of local external physics perturbation and intermodal dispersion on temperature demodulation results. Moreover, the system can omit the pre-calibration process by using the reference temperature before the temperature measurement. The experimental results of dispersion compensation indicate that the temperature accuracy optimizes from 5.6 ℃ to 1.2 ℃, and the temperature uncertainty decreases from 16.8 ℃ to 2.4 ℃. Moreover, the double-end configuration can automatically compensate the local external physics perturbation of the sensing fiber, which exhibits a distinctive improvement.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Zhang Yuxia   Yang Yilun   Zhang Lianhan   Lu Dazhi   Xu Min   Hang Yin   Yan Shishen   Yu Haohai   Zhang Huaijin  

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Praseodymium ion doped gain materials have the superiority of lasing at various visible wavelengths directly. Simple and compact visible lasers are booming with the development of blue laser diodes in recent years. In this paper, we demonstrate the watt level red laser with a single blue laser diode and Pr:YLF crystal. On this basis, the passively Q-switched pulse lasers are obtained with monolayer graphene and Co:ZnO thin film as the Q-switchers in the visible range.

       PDF全文 (下载：6)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Wang Meng   Wang fan   Feng Suya   Yu Chunlei   Wang Shikai   Zhou Qinling   Zhang Lei   Lou Fengguang   Chen Danping   Hu Lili  

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A large-mode-area (LMA) ytterbium doped photonic crystal fiber (PCF) with core NA of 0.034 and core diameter of 50 μm was made by stack-and-draw technique. The core is formed by Yb3+/Al3+/F-/P5+ co-doped silica glass containing 0.09 mol% Yb2O3 with absorption coefficient at 976 nm up to 3.2 dB/m. The core glass with homogeneous distribution of Yb3+ ions and refractive index difference of 4×10-4 compared with pure silica was prepared by sol-gel method and heat homogenization at 2000°C. Laser power amplification of this LMA PCF was studied using a seed source of 21 picosecond pulse duration and 48.7MHz repetition rate at 1030 nm wavelength. With pump power of 520 W, a maximum 272 W (266 KW peak power) quasi single-mode laser output with M2 of 2.2 was achieved in a 4.7 m fiber length bent at a diameter of 47 cm with slope efficiency of 52%, and no obvious mode instability, SRS or thermal damage on end facet of fiber were observed.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Ruan Cunjun   Kong Deyin   Dai Jun   Chen Kanglong   Guo Sujie   Wu Xiaojun  

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The high-resolution frequency domain spectroscopy (FDS) is set up using coherent and continuous wave terahertz emitter and receiver. Terahertz waves are generated and detected by two photomixers with two distributed feedback (DFB) lasers. Atmospheric water vapor with different relative humidity is systematically investigated by the FDS. A high frequency resolution of ~14 MHz is obtained with the help of Hilbert transformation, leading a well resolved and distinct transmittance characterization of water vapor. Compared with conventional THz time domain spectroscopy (TDS), the high-resolution continuous wave THz spectrometer is one of the most practical system in gas-phase molecular sensing, identification, and monitoring.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Li Zhigang   Yang Rui   Sun Meiyu   Han Jing   Zhang Dengying   chen jiannong   Zhang Dawei   Zhu Linwei  

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In this letter, we propose a simple and effective approach for transforming conventional Talbot array illuminator (TAI) with multilevel phase steps into a binary-phase Talbot array illuminator (BP-TAI) through the detour phase encoding. The BP-TAI is a binary (0 π) phase-only diffractive optical element, which can be utilized to generate a large-scale focal spots array with a high compression ratio. As an example, we design a square BP-TAI with the fraction parameter β=15 for achieving a square multifocal lattice with a high compression ratio β^2. Theoretical analysis and experimental results demonstrate that the detour phase encoding is efficient for designing the BP-TAI, especially with the high compression ratio. Such results may be exploited in practical large-scale optical trapping and X-ray imaging.

       PDF全文 (下载：12)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Ruan Zuliang   Pei Li   Zheng Jingjing   Wang JianShuai   Wu Liangying   Ning Tigang   Wang Ji  

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A refractive index intensity detecting sensor with long-period grating written in the single mode - thin core - single mode fiber structure is proposed and optimized theoretically. The sensor is composed of two single-mode fibers connected by a section of long period fiber grating fabricated on thin-core fiber. After optimization and benefit from phase matching point, the loss peak of the structure can reach to 62.8dB theoretically. The wavelength of the characteristic peak is fixed at the phase matching point, so the intensity detection can be achieved. The sensitivity can reach to 272.5dB/RIU. The structural optimization of this paper provides a reference for the fabrication of an easy-made all-fiber sensor without extra cladding.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第7期 pp.07      

Li Min   Liu Xin   Zhang Ang   Xian Hao  

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The precise alignment of high-performance telescope is a key factor to ensure the imaging quality. However, for telescopes with wide field of view, the images are sometimes under-sampled. To study the effects of under-sampled images on the precision of telescope alignment, numerical simulations are implemented with stochastic parallel gradient descent (SPGD) algorithm. The results show that the alignment program can converge stably and quickly. However, with the reduction of full width at half maximum (FWHM) of images, the relative residual errors increase from 9.5% to 19.5%, and the wavefront errors raise from 0.0972λ to 0.1074λ, indicating the accuracy of alignment decreases.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Zheng Yu   Sun Fang-Wen  

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Forward-scattering-light interferometry has become the most commonly used position detection scheme in optical levi-tation system. Usually, 3-set detectors are required to obtain the 3-dimensional motion information. Here, we simplify the 3-set detectors to one set by inserting a Dove prism. With an optical levitation system in vacuum, we investigate the role of Dove prism in the position measurement process. The relationship between power spectral density and ro-tation angle of Dove prism is experimentally demonstrated and analyzed. This work shows that the Dove prism can much reduce the complexity of experimental setup, which can be applied in the compact optical levitation system for studies in metrology, quantum physics and biology.

       PDF全文 (下载：12)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Hou Zhi-Shan   Cao Jia-Ji   Li Aiwu   Yang Han  

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Based on natural protein materials, a series of lenses with different height and focal length were assembled on glass substrates by femtosecond laser non-contact, masking and cold processing. This lens array itself possesses unique and characteristic optical performance in three-dimensional parallel imaging and bending imaging. What is more profound is that by using equilibrium swelling of protein-hydrogel, once the lens array was placed in liquid environment, with the change of ion concentration (eg. pH), the refractive index and curvature of the protein-hydrogel would change, which leads to the flex of focal plane of the lens, finally realizes the dynamically tunable of protein microlens. These smart stress device may have great potential in optical biosensing and microfluidic chip integrated field.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Wu Chenchen   Liu Ning   Hu Hai   Guo Xiangdong   Liao Baoxin   Liu Jiaming   Wang Liming   Chen Chunying   Yang Xiaoxia   Dai Qing  

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Abstract: Monitoring the chemical and structural changes in protein side chains and endpoints by infrared spectroscopy is important to study the chemical reaction and physical adsorption process of proteins. However, the detection of side chains and endpoints in nanoscale proteins is still challenging due to its weak infrared response. Here, by designing a double-layered graphene plasmon sensor on MgF2/Si substrate in the IR fingerprint region, we detect the vibrational modes in side chains and endpoints (1397 cm-1 and 1458 cm-1) of monolayer protein. The sensor could be applied on biochemistry to investigate the physical and chemical reaction of biomolecules.

       PDF全文 (下载：9)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Pan Yijie   Liao Wenhan   Wang He   Yao Yan   Cai Jinhui   Qu Jifeng  

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Atomic Doppler broadening thermometry(DBT) potentially is an accurate and practical approach for the thermodynamic temperature measurement. However, previous reported atomic DBT had a long acquisition time and had only been proved at the triple point of water, 0℃, for the purpose of determination of the Boltzmann constant. This research implemented the Cesium atomic DBT for fast room temperature measurement. Cs133 D1(6S1/2→6p1/2 transition) line was measured by direct laser absorption spectroscopy, and quantity of thermal-induced linewidth broadening was precisely retrieved by the Voigt profile fitting algorithm. The preliminary results showed the proposed approach had a 4 minutes single-scan acquisition time and a 0.2% reproducibility. It is expected that the atomic DBT could be used as an accurate, chip-scale, and calibration-free temperature sensor and standard.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Sun Yuxiang   Wang Mengxia   Wang Xinle   Zhou Ying   Wang Bo   Wang Zhengping   Yu Fapeng   Xu Xinguang  

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With tin diselenide (SnSe2) film as saturable absorber (SA), the passively Q-switched self-frequency doubling (SFD) lasers were realized in Nd3+:ReCa4O(BO3)3 (Re = Y, Gd) crystals. For Nd:YCOB crystal, the maximum average output power at 532 nm was 19.6 mW, and the corresponding pulse repetition frequency, pulse duration, single pulse energy and peak power were 17.6 kHz, 91.9 ns, 1.1 µJ, 12.1 W, respectively. For Nd:GdCOB crystal, these values were 14.5 mW, 22.1 kHz, 48.7 ns, 0.66 µJ and 13.5 W.

       PDF全文 (下载：11)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Hu Hai   Zhao Jianyang   Wang Weimin   Ho James   Kuang Langxing   Liu Wenbin  

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High power LASER diodes (LD) with a lasing wavelength between 700-780 nm have great potential in various medical use. Here we report our recent efforts in developing InGaAsP/AlGaInP based commercial high power edge-emitting LD which has 755 nm emission peak with a world-record continuous wave (CW) output power of 12.7 W, the highest reported so far. The lack of Al atoms in active region significantly lowers the chance of catastrophic optical damage (COD) during high power laser operation. Meanwhile, with accumulated 3800 running hours, our ongoing aging tests reveal excellent reliability of our devices.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Hu Kai   Yi Lilin   Wei Wei   Hu Weisheng  

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We propose a general guideline on the design of stimulated Brillouin scattering (SBS) based microwave photonic filter (MPF) using directly-modulated pump. Filter gain profiles and passband ripples with the waveform repetition periods of the driving current ranging from 2 ns to 100 ns are measured after transmission of different fiber length. The results show that the filter performance has nothing to do with the fiber length and the DAC bandwidth requirement for the driving current is no more than 500MHz. Therefore the low cost, flexible reconfiguration and miniaturization characteristics make SBS filter using directed-modulated pump a promising choice as MPF.

       PDF全文 (下载：13)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Lu Hao   Wu Ying   xie wenjing   tang qi   Han Caiqin   Liu Ying  

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The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using the optical tweezers micromanipulation technology. Firstly, the mechanical properties of irradiated erythrocyte membranes are obtained. Weaker power laser irradiation can delay the decay of the mechanical properties of erythrocytes, and promote the biological activity of erythrocytes, while higher power laser irradiation damages erythrocytes. The stronger the laser irradiation is, the more obvious and rapid the damage will be. The temperature of the cell surface will be changed by regulating the laser power and irradiation time, so the biological functions of erythrocyte can be controlled. Secondly, the finite element simulation of the temperature change on the cell surface under the condition of laser irradiation is carried out using a simulation software, and the precise temperature of the cell surface irradiated cumulatively by a laser with different powers is obtained. Finally, the processes of abscission, unfolding and denaturation of hemoglobins in erythrocytes at different temperatures due to the photothermal effect are analyzed using the model. The mechanism of the laser irradiation on the elasticity of erythrocyte membranes is also obtained.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第6期 pp.06      

Zhang Haifeng   Long Mingliang   Deng Huarong   Wu Zhibo   Chen zhi'en   Zhang Zhongping  

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Space debris laser ranging was achieved with a 60-W, 200-Hz, 532-nm nanosecond slab, single-frequency green laser at the Shanghai Astronomical Observatory's 60-cm satellite laser ranging system. There were 174 passes of space debris measured in 2017, with the minimum radar cross section (RCS) being 0.25 m², and the highest ranging precision up to 13.6 cm. The RCSs of space debris measured with the farthest distances in 174 passes was analyzed. The results show that the farthest measurement distance (R) and RCS (A) was fitting to R=1388.159A^0.24312, indicating that this laser can measure the distance of 1388.159 km at a RCS of 1 m², which is very helpful to surveillance and research on low-Earth-orbit space debris.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

Lu Tingting   Ma Jian   Zhu Xiaolei   Chen Weibiao  

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An external frequency doubling electro-optically Q-switched Nd:YAG 473 nm blue laser was demonstrated. With absorbed pump energy of 48 mJ at 100 Hz repetition rate, about 2 mJ of 473nm blue laser pulse energy was achieved by cascade frequency doubling. The second harmonic conversion efficiency was 64.5% and overall optical-optical efficiency was 4.2%, respectively. The blue laser pulse width was less than 10ns and beam quality factor was less than 2.4.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

Song Wei   Zheng Shanguang   Fu Yanan   Min Changjun   Zhang Yuquan   Xie Zhenwei   Yuan Xiao-Cong (Larry)  

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Controlling both amplitude and phase of light in subwavelength scale is a challenge for traditional optical devices. Here we propose and numerically investigate a novel plasmonic meta-hologram, demonstrating broadband manipulation of both phase and amplitude in subwavelength scale. In the meta-hologram, phase modulation is achieved by the detour phase distribution of unit cells, and amplitude is continuously modulated by a T-shaped nano-cavity with tunable plasmonic resonance. Compared to phase-only hologram, such meta-hologram could reconstruct 3D images with higher signal-to-noise ratio and better image quality, and thus offering great potential in applications such as 3D displays, optical communications, and beam shaping.

       PDF全文 (下载：30)        Chinese Optics Letters ，2019年第17卷第6期 pp.06