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| 1 | Optical vortices 30 years on:OAM manipulation from topological charge to multiple singularities显示文摘Thirty years ago,Coullet et al.proposed that a special optical field exists in laser cavities bearing some analogy with the superfluid vortex.Since then,optical vortices have been widely studied,inspired by the hydrodynamics sharing similar mathematics.Akin to a fluid vortex with a central flow singularity,an optical vortex beam has a phase singularity with a certain topological charge,giving rise to a hollow intensity distribution.Such a beam with helical phase fronts and orbital angular momentum reveals a subtle connection between macroscopic physical optics and microscopic quantum optics.These amazing properties provide a new understanding of a wide range of optical and physical phenomena,including twisting photons,spin–orbital interactions,Bose-Einstein condensates,etc.,while the associated technologies for manipulating optical vortices have become increasingly tunable and flexible.Hitherto,owing to these salient properties and optical manipulation technologies,tunable vortex beams have engendered tremendous advanced applications such as optical tweezers,high-order quantum entanglement,and nonlinear optics.This article reviews the recent progress in tunable vortex technologies along with their advanced applications. | Yijie Shen Xuejiao Wang Zhenwei Xie Changjun Min Xing Fu Qiang Liu Mali Gong Xiaocong Yuan | 2019 | Light(Science & Applications)2019，8，1： | 77 |
| 2 | Optical metasurfaces: new generation building blocks for multi-functional optics显示文摘Optical metasurfaces(OMs)have emerged as promising candidates to solve the bottleneck of bulky optical elements.OMs offer a fundamentally new method of light manipulation based on scattering from resonant nanostructures rather than conventional refraction and propagation,thus offering efficient phase,polarization,and emission control.This perspective highlights state of the art OMs and provides a roadmap for future applications,including active generation,manipulation and detection of light for quantum technologies,holography and sensing. | Dragomir Neshev Igor Aharonovich | 2018 | Light(Science & Applications)2018，7，1： | 13 |
| 3 | Low-loss metasurface optics down to the deep ultraviolet region显示文摘Shrinking conventional optical systems to chip-scale dimensions will benefit custom applications in imaging,displaying,sensing,spectroscopy,and metrology.Towards this goal,metasurfaces-planar arrays of subwavelength electromagnetic structures that collectively mimic the functionality of thicker conventional optical elements-have been exploited at frequencies ranging from the microwave range up to the visible range.Here,we demonstrate highperformance metasurface optical components that operate at ultraviolet wavelengths,including wavelengths down to the record-short deep ultraviolet range,and perform representative wavefront shaping functions,namely,highnumerical-aperture lensing,accelerating beam generation,and hologram projection.The constituent nanostructured elements of the metasurfaces are formed of hafnium oxide-a loss-less,high-refractive-index dielectric material deposited using low-temperature atomic layer deposition and patterned using high-aspect-ratio Damascene lithography.This study opens the way towards low-form factor,multifunctional ultraviolet nanophotonic platforms based on flat optical components,enabling diverse applications including lithography,imaging,spectroscopy,and quantum information processing. | Cheng Zhang Shawn Divitt Qingbin Fan Wenqi Zhu Amit Agrawal Yanqing Lu Ting Xu Henri J.Lezec | 2020 | Light(Science & Applications)2020，9，1： | 11 |
| 4 | Self-configuring universal linear optical component[Invited]显示文摘We show how to design an optical device that can perform any linear function or coupling between inputs and outputs.This design method is progressive,requiring no global optimization.We also show how the device can configure itself progressively,avoiding design calculations and allowing the device to stabilize itself against drifts in component properties and to continually adjust itself to changing conditions.This self-configuration operates by training with the desired pairs of orthogonal input and output functions,using sets of detectors and local feedback loops to set individual optical elements within the device,with no global feedback or multiparameter optimization required.Simple mappings,such as spatial mode conversions and polarization control,can be implemented using standard planar integrated optics.In the spirit of a universal machine,we show that other linear operations,including frequency and time mappings,as well as nonreciprocal operation,are possible in principle,even if very challenging in practice,thus proving there is at least one constructive design for any conceivable linear optical component;such a universal device can also be self-configuring.This approach is general for linear waves,and could be applied to microwaves,acoustics,and quantum mechanical superpositions. | David A.B.Miller | 2013 | Photonics Research2013，1，1： | 10 |
| 5 | Diffraction-limited imaging with monolayer 2D material-based ultrathin flat lenses显示文摘Ultrathin flat optics allow control of light at the subwavelength scale that is unmatched by traditional refractive optics.To approach the atomically thin limit,the use of 2D materials is an attractive possibility due to their high refractive indices.However,achievement of diffraction-limited focusing and imaging is challenged by their thickness-limited spatial resolution and focusing efficiency.Here we report a universal method to transform 2D monolayers into ultrathin flat lenses.Femtosecond laser direct writing was applied to generate local scattering media inside a monolayer,which overcomes the longstanding challenge of obtaining sufficient phase or amplitude modulation in atomically thin 2D materials.We achieved highly efficient 3D focusing with subwavelength resolution and diffractionlimited imaging.The high focusing performance even allows diffraction-limited imaging at different focal positions with varying magnifications.Our work paves the way for downscaling of optical devices using 2D materials and reports an unprecedented approach for fabricating ultrathin imaging devices. | Han Lin Zai-Quan Xu Guiyuan Cao Yupeng Zhang Jiadong Zhou Ziyu Wang Zhichen Wan Zheng Liu Kian Ping Loh Cheng-Wei Qiu Qiaoliang Bao Baohua Jia | 2020 | Light(Science & Applications)2020，9，1： | 9 |
| 6 | On-chip programmable pulse processor employing cascaded MZI-MRR structure显示文摘Optical pulse processor meets the urgent demand for high-speed,ultra wideband devices,which can avoid electrical confinements in various fields,e.g.,alloptical communication,optical computing technology,cohcrcnt control and microwave fields.To date,great efforts have been madc particularly in on-chip programmable pulse proccessing.Here,we experimentally demonstrate a programmable pulse proceesor employing 16cascaded Mach-Zehnder interferometer coupled microring resonator(MZI-MRR)structure based on silicon-oninsulator wafer.With micro-heaters loaded to the device,both amplitude and frequency tunings can be realized in each MZI-MRR unit.Thanks to its reconfigurability and integration ability,First,it can serve as a fractional differentiator whose tuning range is 0.51-2.23 with deviation no more than 7%.Second,the device can be tuned into a programmable optical filter whose bandwidth varies from 0.15to 0.97nm.The optical filter is also shape tunable.Especially,15-channel wavelength selective switches are generated. | Yuhe ZHAO Xu WANG Dingshan GAO Jianji DONG Xinliang ZHANG | 2019 | Frontiers of Optoelectronics2019，12，2： | 9 |
| 7 | Fabrication of kW-level chirped and tilted fiber Bragg gratings and filtering of stimulated Raman scattering in high-power CW oscillators显示文摘Suppression of stimulated Raman scattering(SRS)by means of chirped and tilted fiber Bragg gratings(CTFBGs)has become a key topic.However,research on high-power systems is still lacking due to two problems.Firstly,after the inscription,there are a large number of hydroxyl compounds and hydrogen molecules in CTFBGs that cause significant heating due to their strong infrared absorption.Secondly,CTFBGs can couple Stokes light from the core to the cladding and the coating,which causes serious heating in the coating of the CTFBG.Aimed at overcoming these bottlenecks,a process that combines constant-low-temperature and variable-high-temperature annealing is used to reduce the thermal slope of the CTFBG.Also,a segmented-corrosion cladding power stripping technology is used on the CTFBG to remove the Stokes light which is coupled to the cladding,which solves the problem of overheating in the coating of the CTFBG.Thereby,a CTFBG with both a kilowatt-level power-carrying load and the ability to suppress SRS in a fiber laser has been developed.Further,we establish a kW-level CW oscillator to test the CTFBG.Experimental results demonstrate that the power-carrying load of the CTFBG is close to 1 kW,the thermal slope is lower than 0.015 ℃/W,and the SRS suppression ratio is nearly 23 dB. | Kerong Jiao Jian Shu Hua Shen Zhiwen Guan Feiyan Yang Rihong Zhu | 2019 | High Power Laser Science and Engineering2019，7，2： | 9 |
| 8 | Multiplication and division of the orbital angular momentum of light with diffractive transformation optics显示文摘We present a method to efficiently multiply or divide the orbital angular momentum(OAM)of light beams using a sequence of two optical elements.The key element is represented by an optical transformation mapping the azimuthal phase gradient of the input OAM beam onto a circular sector.By combining multiple circular-sector transformations into a single optical element,it is possible to multiply the value of the input OAM state by splitting and mapping the phase onto complementary circular sectors.Conversely,by combining multiple inverse transformations,the division of the initial OAM value is achievable by mapping distinct complementary circular sectors of the input beam into an equal number of circular phase gradients.Optical elements have been fabricated in the form of phase-only diffractive optics with high-resolution electron-beam lithography.Optical tests confirm the capability of the multiplier optics to perform integer multiplication of the input OAM,whereas the designed dividers are demonstrated to correctly split up the input beam into a complementary set of OAM beams.These elements can find applications for the multiplicative generation of higher-order OAM modes,optical information processing based on OAM beam transmission,and optical routing/switching in telecom. | Gianluca Ruffato Michele Massari Filippo Romanato | 2019 | Light(Science & Applications)2019，8，1： | 8 |
| 9 | Chip-integrated plasmonic flat optics for mid-infrared full-Stokes polarization detection显示文摘Flat optics presents a new path to control the phase, amplitude, and polarization state of light with ultracompact devices. Here we demonstrate chip-integrated metasurface devices for polarization detection of mid-infrared light with arbitrary polarization states. Six high-performance microscale linear and circular polarization filters based on vertically stacked plasmonic metasurfaces(with total thickness <600 nm) are integrated on the same chip to obtain all four Stokes parameters of light with high accuracy. The device designs can be tailored to operate at any wavelength in the mid-infrared spectral region and are feasible for on-chip integration with mid-infrared(mid-IR) photodetectors and imager arrays. Our work will enable on-chip mid-IR polarimeters and polarimetric imaging systems, which are highly desirable for many applications, such as clinical diagnosis, target detection, and space exploration. | JING BAI CHU WANG XIAHUI CHEN ALI BASIRI CHAO WANG YU YAO | 2019 | Photonics Research2019，7，9： | 8 |
| 10 | The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)显示文摘The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST's special design allows both a large aperture (effective aperture of 3.6 m-4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror's surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. | Xiang-Qun Cui Yong-Heng Zhao Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou | 2012 | Research in Astronomy and Astrophysics2012，12，9： | 8 |
| 11 | 密度分布函数在聚类算法中的应应用用显示文摘深入分析了传统的基于密度的聚类方法的特点和存在的问题及讨论了基于密度聚类算法研究现状,提出了一种改进的基于密度分布函数的聚类算法.使用K最近邻(KNN)的思想度量密度以寻找当前密度最大点,即中心点.并使用区域比例,将类从中心点开始扩展,每次扩展的同时引入半径比例因子以发现核心点.再从该核心点的KNN扩展类,直至密度下降到中心点密度的给定比率时结束.给出了数个算法实例并与基于网格的共享近邻聚类(GNN)算法在聚类准确率和效率上进行了试验比较,试验表明该算法极大降低了基于密度聚类算法对参数的敏感性、改善了对高维密度分布不均数据集的聚类效果、提高了聚类准确率和效率. | 谭建豪 章兢 李伟雄 | 2011 | 控制理论与应用2011，28，12： | 8 |
| 12 | Malus-metasurface-assisted polarization multiplexing显示文摘Polarization optics plays a pivotal role in diffractive,refractive,and emerging flat optics,and has been widely employed in contemporary optical industries and daily life.Advanced polarization manipulation leads to robust control of the polarization direction of light.Nevertheless,polarization control has been studied largely independent of the phase or intensity of light.Here,we propose and experimentally validate a Malus-metasurface-assisted paradigm to enable simultaneous and independent control of the intensity and phase properties of light simply by polarization modulation.The orientation degeneracy of the classical Malus’s law implies a new degree of freedom and enables us to establish a one-to-many mapping strategy for designing anisotropic plasmonic nanostructures to engineer the Pancharatnam–Berry phase profile,while keeping the continuous intensity modulation unchanged.The proposed Malus metadevice can thus generate a near-field greyscale pattern,and project an independent far-field holographic image using an ultrathin and single-sized metasurface.This concept opens up distinct dimensions for conventional polarization optics,which allows one to merge the functionality of phase manipulation into an amplitudemanipulation-assisted optical component to form a multifunctional nano-optical device without increasing the complexity of the nanostructures.It can empower advanced applications in information multiplexing and encryption,anti-counterfeiting,dual-channel display for virtual/augmented reality,and many other related fields. | Liangui Deng Juan Deng Zhiqiang Guan Jin Tao Yang Chen Yan Yang Daxiao Zhang Jibo Tang Zhongyang Li Zile Li Shaohua Yu Guoxing Zheng Hongxing Xu Cheng-Wei Qiu Shuang Zhang | 2020 | Light(Science & Applications)2020，9，1： | 7 |
| 13 | Teleporting N-qubit unknown atomic state by utilizing the V-type three-level atom显示文摘Realizing the teleportation of quantum state, especially the teleportation of N-qubit quantum state, is of great importance in quantum information. In this paper, Raman-interaction of the V-type degenerate three-level atom and single-mode cavity field is studied by utilizing complete quantum theory. Then a new scheme for teleporting N-qubit unknown atomic state via Raman-interaction of the V-type degenerate three-level atom with a single-mode cavity field is proposed, which is based upon the complete quantum theory mentioned above. | ZHANG XinHua YANG ZhiYong XU PeiPei | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，7： | 7 |
| 14 | Powerful terahertz waves from long-wavelength infrared laser filaments显示文摘Strong terahertz(THz)electric and magnetic transients open up new horizons in science and applications.We review the most promising way of achieving sub-cycle THz pulses with extreme field strengths.During the nonlinear propagation of two-color mid-infrared and far-infrared ultrashort laser pulses,long,and thick plasma strings are produced,where strong photocurrents result in intense THz transients.The corresponding THz electric and magnetic field strengths can potentially reach the gigavolt per centimeter and kilotesla levels,respectively.The intensities of these THz fields enable extreme nonlinear optics and relativistic physics.We offer a comprehensive review,starting from the microscopic physical processes of light-matter interactions with mid-infrared and far-infrared ultrashort laser pulses,the theoretical and numerical advances in the nonlinear propagation of these laser fields,and the most important experimental demonstrations to date. | Vladimir Yu.Fedorov Stelios Tzortzakis | 2020 | Light(Science & Applications)2020，9，1： | 7 |
| 15 | Technology development for ultraintense all-OPCPA systems显示文摘Optical parametric chirped-pulse amplification(OPCPA) [Dubietis et al., Opt. Commun. 88, 437(1992)] implemented by multikilojoule Nd:glass pump lasers is a promising approach to produce ultraintense pulses(>1023 W/cm2).Technologies are being developed to upgrade the OMEGA EP Laser System with the goal to pump an optical parametric amplifier line(EP OPAL) with two of the OMEGA EP beamlines. The resulting ultraintense pulses(1.5 kJ, 20 fs,1024 W/cm2) would be used jointly with picosecond and nanosecond pulses produced by the other two beamlines. A midscale OPAL pumped by the Multi-Terawatt(MTW) laser is being constructed to produce 7.5-J, 15-fs pulses and demonstrate scalable technologies suitable for the upgrade. MTW OPAL will share a target area with the MTW laser(50 J, 1 to 100 ps), enabling several joint-shot configurations. We report on the status of the MTW OPAL system, and the technology development required for this class of all-OPCPA laser system for ultraintense pulses. | J.Bromage S.-W.Bahk I.A.Begishev C.Dorrer M.J.Guardalben B.N.Hoffman J.B.Oliver R.G.Roides E.M.Schiesser M.J.Shoup III M.Spilatro B.Webb D.Weiner J.D.Zuegel | 2019 | High Power Laser Science and Engineering2019，7，1： | 7 |
| 16 | Dielectric metasurfaces for distance measurements and three-dimensional imaging显示文摘Ultrathin metasurfaces have shown the capability to influence all aspects of light propagation.This has made them promising options for replacing conventional bulky imaging optics while adding advantageous optical properties or functionalities.We demonstrate that such metasurfaces can also be applied for single-lens three-dimensional(3-D)imaging based on a specifically engineered point-spread function(PSF).Using Huygens’metasurfaces with high transmission,we design and realize a phase mask that implements a rotating PSF for 3-D imaging.We experimentally characterize the properties of the realized double-helix PSF,finding that it can uniquely encode object distances within a wide range.Furthermore,we experimentally demonstrate wide-field depth retrieval within a 3-D scene,showing the suitability of metasurfaces to realize optics for 3-D imaging,using just a single camera and lens system. | Chunqi Jin Mina Afsharnia RenéBerlich Stefan Fasold Chengjun Zou Dennis Arslan Isabelle Staude Thomas Pertsch Frank Setzpfandt | 2019 | Advanced Photonics2019，1，3： | 7 |
| 17 | Experimental demonstration of single-mode fiber coupling using adaptive fiber couplerExperimental demonstration of single-mode fiber coupling using adaptive fiber couplerExperimental demonstration of single-mode fiber coupling using adaptive fiber couplerExperimental demonstration of single-mode fiber coupling using adaptive fiber coupler显示文摘Coupling plane wave into a single-mode fiber (SMF) with high and steady coupling efficiency is crucial for fiber- based free-space laser systems, where random angular jitters are the main influencing factors of fiber coupling. In this paper, we verified a new adaptive-optic device named adaptive fiber coupler (AFC) which could compensate angular jitters and improve the SMF coupling efficiency in some degree. Experiments of SMF coupling under the angular jitter situation using AFC have been achieved. Stochastic parallel gradient descent (SPGD) algorithm is employed as the control strategy, of which the iteration rate is 625 Hz. In closed loop, the coupling efficiency keeps above 65% when angular errors are below 80/3tad. The compensation bandwidth is 35 Hz at sine-jitter of 15 ~rad amplitude with average coupling efficiency of above 60%. Also, experiments with simulated turbulence have been studied. The average coupling efficiency increases from 31.97% in open loop to 61.33% in closed loop, and mean square error (MSE) of coupling efficiency drops from 7.43% to 1.75%. | 罗文 耿超 武云云 谭毅 罗奇 刘红梅 李新阳 | 2014 | Chinese Physics B2014，23，1： | 6 |
| 18 | A low-noise, high-SNR balanced homodyne detector for the bright squeezed state measurement in 1–100 kHz range显示文摘We report a low-noise, high-signal-to-noise-ratio(SNR) balanced homodyne detector based on the standard transimpedance amplifier circuit and the inductance and capacitance combination for the measurement of the bright squeezed state in the range from 1 kHz to 100 kHz. A capacitance is mounted at the input end of the AC branch to prevent the DC photocurrent from entering the AC branch and avoid AC branch saturation. By adding a switch at the DC branch,the DC branch can be flexibly turned on and off on different occasions. When the switch is on, the DC output provides a monitor signal for laser beam alignment. When the switch is off, the electronic noise of the AC branch is greatly reduced at audio-frequency band due to immunity to the impedance of the DC branch, hence the SNR of the AC branch is significantly improved. As a result, the electronic noise of the AC branch is close to -125 dBm, and the maximum SNR of the AC branch is 48 dB with the incident power of 8 mW in the range from 1 kHz to 100 kHz. The developed photodetector paves a path for measuring the bright squeezed state at audio-frequency band. | 王锦荣 王庆伟 田龙 苏静 郑耀辉 | 2020 | Chinese Physics B2020，29，3： | 6 |
| 19 | Freeform imaging systems:Fermat's principle unlocks'first time right'design显示文摘For more than 150 years,scientists have advanced aberration theory to describe,analyze and eliminate imperfections that disturb the imaging quality of optical components and systems.Simultaneously,they have developed optical design methods for and manufacturing techniques of imaging systems with ever-increasing complexity and performanee up to the point where they are now including optical elements that are unrestricted in their surface shape.These so-called optical freeform elements offer degrees of freedom that can greatly extend the functionalities and further boost the specifications of state-of-the-art imaging systems.However,the drastically increased number of surface coefficients of these freeform surfaces poses severe challenges for the optical design process,such that the deployme nt of freeform optics remained limited until today.In this paper,we present a deterministic direct optical design method for freeform imaging systems based on differential equations derived from Fermats principle and solved using power series.The method allows calculating the optical surface coefficients that ensure minimal image blurring for each individual order of aberrations.We demonstrate the systematic,deterministic,scalable,and holistic character of our method with catoptric and catadioptric design examples.As such we introduce a disruptive methodology to design optical imaging systems from scratch,we largely reduce the 'trial-and-error',approach in present-day optical design,and we pave the way to a fast-track uptake of freeform elements to create the nextgeneratio n high-end optics.We include a user application that allows users to experience this unique design method hands-on. | Fabian Duerr Hugo Thienpont | 2021 | Light(Science & Applications)2021，10，6： | 5 |
| 20 | Design and analysis of extended depth of focus metalenses for achromatic computational imaging显示文摘Metasurface optics have demonstrated vast potential for implementing traditional optical components in an ultracompact and lightweight form factor.Metasurfaces,however,suffer from severe chromatic aberrations,posing serious limitations on their practical use.Eixisting approaches for circumventing this involving dispersion engineering are limited to small apertures and often entail multiple scatterers per unit cell with small feature sizes.Here,we prescnt an alternative technique to mitigatc chromatic aberration and demonstrate high-quality,full-color imaging using extended depth of focus(EDOF)metalenses and computational reconstruction.Previous EDOF metalenses have relied on cubic phase masks,where the image quality suffers from asymmetric artefacts.Here we demonstrate the use of rotationally symmetric masks,including logarithmic-aspherical,and shifted axicon masks,to mitigate this problem.Our work will inspire further development in achromatic metalenses beyond dispersion engineering and hybrid optical-digital metasurface systems. | LUOCHENG HUANA JAMES WHITEHEAD SHANE COLBURN ARKA MAJUMDAR | 2020 | Photonics Research2020，8，10： | 5 |
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