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5G Flexible Optical Transport Networks with Large-Capacity, Low-Latency and High-Efficiency 预览
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作者 Yuefeng Ji Jiawei Zhang +1 位作者 Yuming Xiao Zhen Liu 《中国通信:英文版》 SCIE CSCD 2019年第5期19-32,共14页
The fifth generation(5G) of mobile communications are facing big challenges, due to the proliferation of diversified terminals and unprecedented services such as internet of things(IoT), high-definition videos, virtua... The fifth generation(5G) of mobile communications are facing big challenges, due to the proliferation of diversified terminals and unprecedented services such as internet of things(IoT), high-definition videos, virtual/augmented reality(VR/AR). To accommodate massive connections and astonish mobile traffic, an efficient 5G transport network is required. Optical transport network has been demonstrated to play an important role for carrying 5G radio signals. This paper focuses on the future challenges, recent studies and potential solutions for the 5G flexible optical transport networks with the performances on large-capacity, low-latency and high-efficiency. In addition, we discuss the technology development trends of the 5G transport networks in terms of the optical device, optical transport system, optical switching, and optical networking. Finally, we conclude the paper with the improvement of network intelligence enabled by these technologies to deterministic content delivery over 5G optical transport networks. 展开更多
关键词 5G OPTICAL TRANSPORT NETWORKS OPTICAL devices OPTICAL TRANSPORT system OPTICAL SWITCHING OPTICAL NETWORKING
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Twisted optical communications using orbital angular momentum
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作者 Jian Wang 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第3期1-21,共21页
Angular momentum,a fundamental physical quantity,can be divided into spin angular momentum(SAM)and orbital angular momentum(OAM)in electromagnetic waves.Helically-phased or twisted light beams carrying OAM that exploi... Angular momentum,a fundamental physical quantity,can be divided into spin angular momentum(SAM)and orbital angular momentum(OAM)in electromagnetic waves.Helically-phased or twisted light beams carrying OAM that exploit the spatial structure physical dimension of electromagnetic waves have benefited wide applications ranging from optical manipulation to quantum information processing.Using the two distinct properties of OAM,i.e.,inherent orthogonality and unbounded states in principle,one can develop OAM modulation and OAM multiplexing techniques for twisted optical communications.OAM multiplexing is an alternative space-division multiplexing approach employing an orthogonal mode basis related to the spatial phase structure.In this paper,we review the recent progress in twisted optical communications using OAM in free space and fiber.The basic concept of momentum,angular momentum,SAM,OAM and OAM-carrying twisted optical communications,key techniques and devices of OAM generation/(de)multiplexing/detection,high-capacity spectrally-efficient free-space OAM links,fiber-based OAM links,and OAM processing functions are presented.Ultra-high spectral efficiency and petabit-scale freespace data links are achieved benefiting from OAM multiplexing.The key techniques and challenges of twisted optical communications are also discussed.Twisted optical communications using OAM are compatible with other existing physical dimensions such as frequency/wavelength,amplitude,phase,polarization and time,opening a possible way to facilitate continuous increase of the aggregate transmission capacity and spectral efficiency through N-dimensional multiplexing. 展开更多
关键词 fiber OPTICAL COMMUNICATIONS FREE-SPACE OPTICAL COMMUNICATIONS modulation MULTIPLEXING orbital angular momentum space-division MULTIPLEXING spectral efficiency TWISTED OPTICAL COMMUNICATIONS TWISTED LIGHT structured LIGHT
Analysis and testing of toted ionizing dose effect on several commercial optical transceivers via gamma-ray radiation
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作者 展月英 何建华 +1 位作者 王斐 王立芊 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第5期78-83,共6页
In our Lett er, we selec ted several commercial optical t ransceivers, which consist of single-channel transceiver modules, parallel transmitting and receiving modules, and Ethernet passive optical network (EPON) opti... In our Lett er, we selec ted several commercial optical t ransceivers, which consist of single-channel transceiver modules, parallel transmitting and receiving modules, and Ethernet passive optical network (EPON) optical linet erminal (OLT) and optical net work unit (ONU) modules, to do the total ionizing dose (TID) testing via the gamma-ray radiation method. The changing of current and receiver sensitivity of optical transceivers is discussed and analyzed. Based on the TID testing exposed to a TID of 50 krad (Si) at a dose rate of about 0.1 rad (Si)/s, the performance of single-channel transceivers and parallel receiving modules has not changed after 50 krad (Si) exposure, the parallel transmitting and EPON ONU modules have not worked after 40 krad (Si) and 47 krad (Si) exposure, the EPON OLT module has bit error in the process of irradiation, and it can work well after annealing;the reason for the error of OLT is analyzed. Finally, based on the theoretical analysis and testing results, this Letter provides several design suggestions to improve the reliability for optical transceivers, which can be referenced by satellite system designation for various space missions. 展开更多
关键词 ETHERNET PASSIVE OPTICAL network(EPON) OPTICAL linet erminal(OLT) OPTICAL net work unit(ONU)
Review of optical tweezers in vacuum
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作者 Nan LI Xun-min ZHU +3 位作者 Wen-qiang LI Zhen-hai FU Meng-zhu HU Hui-zhu HU 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第5期655-673,共19页
As a versatile tool for trapping and manipulating neutral particles, optical tweezers have been studied in a broad range of fields such as molecular biology, nanotechnology, and experimentally physics since Arthur Ash... As a versatile tool for trapping and manipulating neutral particles, optical tweezers have been studied in a broad range of fields such as molecular biology, nanotechnology, and experimentally physics since Arthur Ashkin pioneered the field in the early 1970 s. By levitating the "sensor" with a laser beam instead of adhering it to solid components, excellent environmental decoupling is achieved. Furthermore, unlike levitating particles in liquid or air, optical tweezers operating in vacuum are isolated from environmental thermal noise, thus eliminating the primary source of dissipation present for most inertial sensors. This attracted great attention in both fundamental and applied physics. In this paper we review the history and the basic concepts of optical tweezers in vacuum and provide an overall understanding of the field. 展开更多
关键词 OPTICAL TWEEZERS OPTICAL TRAPPING in VACUUM OPTICAL COOLING
Metalens in harmony with refractive optics
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作者 Xueyi Zhu Shuming Wang +1 位作者 Xuejun Yan Minghui Lu 《科学通报:英文版》 SCIE EI CSCD 2019年第12期797-798,共2页
Optical dispersion is an inherent property of all materials in nature. Due to the dispersion of the optical material and the phase accumulation of the light field at different wavelengths, chromatic aberration is inev... Optical dispersion is an inherent property of all materials in nature. Due to the dispersion of the optical material and the phase accumulation of the light field at different wavelengths, chromatic aberration is inevitable in commercial optical lens. When taking pictures by lenses with severe chromatic aberration, the images will look blurred or noticeably colored edges (red, green, blue) around the objects, especially in high-contrast situations. Thus, achromatism, correction of the chromatic aberration, is extremely important in broadband optical applications. There are mainly two approaches in the correction of the chromatic aberration in existing optical systems: combining the refractive lenses with different dispersions or introducing the diffractive optical elements. However, it is still a technical challenge to achieve that goal in the entire visible light band. 展开更多
关键词 OPTICAL DISPERSION OPTICAL MATERIAL different WAVELENGTHS
On the development of optical peripheral nerve interfaces 预览
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作者 Hans E.Anderson Richard F.ff.Weir 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第3期425-436,共12页
Limb loss and spinal cord injury are two debilitating conditions that continue to grow in prevalence.Prosthetic limbs and limb reanimation present two ways of providing affected individuals with means to interact in t... Limb loss and spinal cord injury are two debilitating conditions that continue to grow in prevalence.Prosthetic limbs and limb reanimation present two ways of providing affected individuals with means to interact in the world.These techniques are both dependent on a robust interface with the peripheral nerve.Current methods for interfacing with the peripheral nerve tend to suffer from low specificity,high latency and insufficient robustness for a chronic implant.An optical peripheral nerve interface may solve some of these problems by decreasing invasiveness and providing single axon specificity.In order to implement such an interface three elements are required:(1)a transducer capable of translating light into a neural stimulus or translating neural activity into changes in fluorescence,(2)a means for delivering said transducer and (3)a microscope for providing the stimulus light and detecting the fluorescence change.There are continued improvements in both genetically encoded calcium and voltage indicators as well as new optogenetic actuators for stimulation.Similarly,improvements in specificity of viral vectors continue to improve expression in the axons of the peripheral nerve.Our work has recently shown that it is possible to virally transduce axons of the peripheral nerve for recording from small fibers.The improvements of these components make an optical peripheral nerve interface a rapidly approaching alternative to current methods. 展开更多
关键词 PERIPHERAL NERVE INTERFACES optogenetics OPTICAL neural interface OPTICAL PERIPHERAL NERVE interface GCaMP ArcLight adenoassociated VIRAL vector lentiviral VECTORS VIRAL VECTORS implantable microscopy
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A review of multiple optical vortices generation: methods and applications
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作者 Long ZHU Jian WANG 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期52-68,共17页
Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical ... Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical communications.In various optical vortices enabled applications,the generation of multiple optical vortices is of great importance.In this review article,we focus on the methods of multiple optical vortices generation and its applications.We review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM modes.Diverse applications of multiple OAM modes in optical communications and non-communication areas are presented.Future trends,perspectives and opportunities are also discussed. 展开更多
关键词 OPTICAL communications OPTICAL VORTICES ORBITAL angular momentum (OAM) mode-division MULTIPLEXING (MDM) MODE MULTICASTING
Advances in narrow linewidth diode lasers
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作者 Xingkai LANG Peng JIA +7 位作者 Yongyi CHEN Li QIN Lei LIANG Chao CHEN Yubing WANG Xiaonan SHAN Yongqiang NING Lijun WANG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期21-33,共13页
The smart travel era has come and requirement for high precision lidar detection technology is higher and higher. The new solid-state lidars can meet the requirements of intelligent cars in the future, with the advant... The smart travel era has come and requirement for high precision lidar detection technology is higher and higher. The new solid-state lidars can meet the requirements of intelligent cars in the future, with the advantages of high resolution, strong anti-active jamming ability, small volume, light weight, low cost and so on. The narrow linewidth diode laser is the perfect light source of solid-state lidars. The progress and development of narrow linewidth diode laser technique can greatly improve the application of solidstate lidar. The technology and development status of narrow linewidth diode lasers has been described detailly in the paper. And the design ideas, key fabrication technologies and optical characteristics of various narrow linewidth diode lasers have been analyzed and discussed as well. Finally, the developments of narrow linewidth diode lasers are prospected. 展开更多
关键词 diode lasers narrow LINEWIDTH internal CAVITY OPTICAL FEEDBACK TECHNOLOGY external CAVITY OPTICAL FEEDBACK TECHNOLOGY SOLID-STATE lidar
Error correction for short-range optical interconnect using COTS transceivers
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作者 Ziyuan ZHENG Chuanchuan YANG +1 位作者 Dan ZHAO Ziyu WANG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期72-78,共7页
Nowadays, quantities of commercial off-the-shelf(COTS) optical transceivers are widely equipped in both exiting and abuilding data centers. As data centers are becoming larger and containing more servers, the method t... Nowadays, quantities of commercial off-the-shelf(COTS) optical transceivers are widely equipped in both exiting and abuilding data centers. As data centers are becoming larger and containing more servers, the method to ensure longer and steady transmission with COTS optical transceivers becomes one of the key issues. Meanwhile, variations in the manufacturing of COTS optical transceivers bring in fluctuation of packet error rate(PER) in communication. In this paper, we present an application layer adaptive forward error correction(AL-AFEC) coding scheme for COTS optical transceivers in optical interconnect to solve the problems mentioned above and test its performance in a 10 Gbps Ethernet(10 GbE)link using 10 GBASE-SR SFP+ modules. Experimental results show that the proposed scheme enables longer transmission distance and the instability introduced by manufactural variations is well settled. Since our scheme requires no extra hardware on optical transceivers, it is a considerable low-cost alternative to improve system reliability and achieve longer transmission distance for COTS optical transceivers. 展开更多
关键词 SHORT-RANGE OPTICAL interconnect vertical cavity surface emitting laser(VCSEL) ethernet application layer adaptive forward error correction commercial off-the-shelf OPTICAL transceiver
Formulation of Determining the Gravity Potential Difference Using Ultra-High Precise Clocks via Optical Fiber Frequency Transfer Technique
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作者 Ziyu Shen Wen-Bin Shen +3 位作者 Zhao Peng Tao Liu Shougang Zhang Dingbo Chao 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期422-428,共7页
Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by r... Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by remote comparison of two precise optical clocks via optical fiber frequency transfer. After synchronization, by measuring the signal’s frequency shift based upon the comparison of bidirectional frequency signals from P and Q oscillators connected with two optical atomic clocks via remote optical fiber frequency transfer technique, the geopotential difference between the two points could be determined, and its accuracy depends on the stabilities of the optical clocks and the frequency transfer comparison technique. Due to the fact that the present stability of optical clocks achieves 1.6×10-18 and the present frequency transfer comparison via optical fiber provides stabilities as high as 10-19 level, this approach is prospective to determine geopotential difference with an equivalent accuracy of 1.5 cm. In addition, since points P and Q are quite arbitrary, this approach may provide an alternative way to determine the geopotential over a continent, and prospective potential to unify a regional height datum system. 展开更多
关键词 GRAVITY FREQUENCY shift OPTICAL fiber FREQUENCY TRANSFER OPTICAL CLOCK GRAVITY potential
Hollow and filled fiber bragg gratings in nano-bore optical fibers
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作者 张永欣 梁生 +9 位作者 余倩卿 廉正刚 董梓年 王旋 林裕勤 邹郁祁 邢坤 梁柳雁 赵小艇 涂立静 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期279-285,共7页
To combine the technical functions and advantages of solid-core fiber Bragg gratings(FBGs) and hollow-core optical fibers(HCFs), the hollow and filled FBGs in nano-bore optical fibers(NBFs) with nano-bore in the GeO2-... To combine the technical functions and advantages of solid-core fiber Bragg gratings(FBGs) and hollow-core optical fibers(HCFs), the hollow and filled FBGs in nano-bore optical fibers(NBFs) with nano-bore in the GeO2-doped core are proposed.The fundamental mode field, effective mode index, and confinement loss of NBF with 50 nm–7 μm-diameter hollow and filled nano-bore are numerically investigated by the finite element method.The reflected spectra of FBGs in NBFs are obtained by the transmission matrix method.The hollow FBGs in NBFs can be acheived with ~5% power fraction in the bore and the ~0.9 reflectivity when bore diameter is less than 3 μm.The filled FBGs can be realized with~1% power fraction and 0.98 reflectivity with different fillings including o-xylene, trichloroethylene, and chloroform for 800-nm bore diameter.The feasibility of the index sensing by our proposed NBF FBG is also analyzed and discussed.The experimental fabrication of hollow and filled FBGs are discussed and can be achieved by current techniques.The aim of this work is to establish a principle prototype for investigating the HCFs and solid-core FBGs-based fiber-optic platforms,which are useful for applications such as the simultaneous chemical and physical sensing at the same position. 展开更多
关键词 nano-bore OPTICAL FIBER FIBER Bragg grating(FBG) hollow-core OPTICAL fiber(HCF) FIBER optics
Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study 预览
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作者 Osman OguzAhsen Kaicheng Liang +3 位作者 Hsiang-Chieh Lee Zhao Wang James G Fujimoto Hiroshi Mashimo 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第16期1997-2009,共13页
BACKGROUND Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is de... BACKGROUND Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of life. Radiofrequency ablation (RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease management. AIM To study feasibility of optical coherence tomography angiography (OCTA) for investigating subsurface vascular alterations in CRP and response to RFA treatment. METHODS Two patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahighspeed optical coherence tomography (OCT) system over 15 OCT/colonoscopy visits (2 normal patients, 5 RFA-na?ve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, without requiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic scoring. RESULTS OCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 μm in diameter versus abnormal heterogenous enlarged arterioles and ve 展开更多
关键词 OPTICAL COHERENCE TOMOGRAPHY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY Radiofrequency ablation CHRONIC RADIATION proctopathy Rectal telangiectasia density scoring system Subsurface microvascular imaging
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Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients
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作者 Antonio Manuel Garrido-Hermosilla Mariola Méndez-Muros +6 位作者 Estanislao Gutiérrez-Sánchez Cristóbal Morales-Portillo María Jesús Díaz-GrANDa Eduardo Esteban-González Isabel Relimpio-López María Asunción Martínez-Brocca Enrique Rodríguez-de-la-Rúa-Franch 《国际眼科杂志:英文版》 SCIE CAS 2019年第6期985-989,共5页
AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Dem... AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients. 展开更多
关键词 choroidal thickness renal function swept-source OPTICAL COHERENCE TOMOGRAPHY SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY diabetes MELLITUS
Advances in fibre optic based geotechnical monitoring systems for underground excavations 预览
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作者 Hongkui Gong Mehmet S.Kizil +3 位作者 Zhongwei Chen Moe Amanzadeh Ben Yang Saiied M.Aminossadati 《矿业科学技术学报:英文版》 CSCD 2019年第2期229-238,共10页
Geotechnical stability is a major concern for the long-term safety and integrity of underground infrastructures such as tunnels,railway stations,mine shafts and hydraulic power chambers.An effective geotechnical monit... Geotechnical stability is a major concern for the long-term safety and integrity of underground infrastructures such as tunnels,railway stations,mine shafts and hydraulic power chambers.An effective geotechnical monitoring system is able to provide adequate warning to underground personnel prior to any unexpected major geotechnical failure.This paper reviews the conventional geotechnical monitoring sensors and the emerging Fibre Optic Sensing(FOS)techniques,pointing out their unique features and major differences.Recent advances in various FOS based monitoring systems,including Brillouin time domain distributed optical sensors and fibre Bragg grating(FBG)sensors,are investigated through a critical review of the laboratory studies and field applications used for underground geotechnical monitoring.Particular emphasis is given to fibre packaging,temperature compensation,installation methods and instrumentation performance in the underground environment.A detailed discussion of the advantages and limitations of each FOS monitoring system is also presented in this paper. 展开更多
关键词 Underground GEOTECHNICAL monitoring Conventional GEOTECHNICAL instruments Distributed OPTICAL FIBRE sensors FIBRE BRAGG GRATING BRILLOUIN OPTICAL analysis
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Characterization of focusing performance of spiral zone plates with fractal structure
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作者 臧华平 郑程龙 +10 位作者 吉子雯 范全平 魏来 李永杰 牧凯军 陈述 王传珂 朱效力 谢常青 曹磊峰 梁二军 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期184-188,共5页
We propose an efficient method of generating a vortex beam with multi-foci by using a fractal spiral zone plate(FSZP), which is designed by combining fractal structure with a spiral zone plate(SZP) in the squared radi... We propose an efficient method of generating a vortex beam with multi-foci by using a fractal spiral zone plate(FSZP), which is designed by combining fractal structure with a spiral zone plate(SZP) in the squared radial coordinate.The theoretical analysis reveals that the number of foci that embed vortices is significantly increased as compared with that obtained by using a conventional SZP. Furthermore, the influence of topological charge on the intensity distribution in focal plane is also discussed in detail. For experimental investigation, an FSZP with topological charge p = 1 and 6.4 mm diameter is fabricated by using a photo-etching technique. The calibration indicates that the focusing performances of such a kind of zone plane(ZP) accord well with simulations, thereby providing its potential applications in multi-dimensional optical manipulation and optical imaging technology. 展开更多
关键词 OPTICAL VORTICES SPIRAL ZONE PLATE DIFFRACTIVE OPTICAL elements
Efficient improvement of 2.7 μm luminescence of Er3+:oxyfluoride glass containing gallium by Yb3+ ions codoping
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作者 Yapei Peng Xinqiang Yuan +3 位作者 Long Zhang Peiguang Yan Wenfei Zhang Shuangchen Ruan 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第5期487-491,共5页
Mid-infrared laser materials with low phonon energy have significant applications. However, the development of available glass systems for high-power laser gain medium have posed a great challenge.Therefore, we invest... Mid-infrared laser materials with low phonon energy have significant applications. However, the development of available glass systems for high-power laser gain medium have posed a great challenge.Therefore, we investigated the 2.7 μm spectroscopic properties of Er3+/Yb3+ -codoped oxyfluoride glass containing gallium, which were prepared by typically melting and quenching methods. The 2.7 μm luminescence properties of the Er3+/Yb3+-codoped oxyfluoride glass containing gallium were recorded by a 980 nm laser diode. The Judde Ofelt parameters, decay curves, emission cross section, energy transfer efficiency and quantum efficiency were calculated. The maximum emission cross section of YbFGa-0.5 is 1.63 × 10-20 cm2 by 980 nm excitation. The energy transfer efficiency is calculated to be77.8% for the YbFGa-0.5 glass around 2700 nm. The quantum efficiency at 1530 nm is 65.6%. The result reveals that the best doping concentration ratio of Er3+:Yb3+ ions is 1:0.5, and suggests an effective energy transfer from Yb3+ to Er3+ ions. 展开更多
关键词 OPTICAL materials OPTICAL spectroscopy RARE-EARTH IONS doped MID-INFRARED Energy transfer
Fiber-based optical trapping and manipulation
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作者 Hongbao XIN Baojun LI 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期97-110,共14页
An optical fiber serves as a versatile tool for optical trapping and manipulation owing to its many advantages over conventional optical tweezers,including ease of fabrication,compact configurations,flexible manipulat... An optical fiber serves as a versatile tool for optical trapping and manipulation owing to its many advantages over conventional optical tweezers,including ease of fabrication,compact configurations,flexible manipulation capabilities,ease of integration,and wide applicability.Here,we review recent progress in fiberbased optical trapping and manipulation,which includes mainly photothermal-based and optical-force-based trapping and manipulation.We focus on five topics in our review of progress in this area: massive photothermal trapping and manipulation,evanescent-field-based trapping and manipulation,dual-fiber tweezers for singlenanoparticle trapping and manipulation,single-fiber tweezers for single-particle trapping and manipulation,and single-fiber tweezers for multiple-particle/cell trapping and assembly. 展开更多
关键词 OPTICAL TRAPPING PHOTOTHERMAL effect OPTICAL FORCE CELL TRAPPING and ASSEMBLY
On-chip programmable pulse processor employing cascaded MZI-MRR structure
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作者 Yuhe ZHAO Xu WANG +2 位作者 Dingshan GAO Jianji DONG Xinliang ZHANG 《中国光电子学前沿:英文版》 EI CSCD 2019年第2期148-156,共9页
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 contr... 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. 展开更多
关键词 integrated optics DEVICES optical processing ALL-OPTICAL DEVICES PULSE shaping
Saturation in wavelength-division multiplexing free-space optical communication systems
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作者 Jeremiah O. BANDELE Malcolm WOOLFSON Andrew J. PHILLIPS 《中国光电子学前沿:英文版》 EI CSCD 2019年第2期197-207,共11页
The performance of a wavelength-division multiplexing (WDM) free-space optical (FSO) commu-nication system in a turbulent atmosphere employing optical amplifiers to improve capacity is investigated, in the presence of... The performance of a wavelength-division multiplexing (WDM) free-space optical (FSO) commu-nication system in a turbulent atmosphere employing optical amplifiers to improve capacity is investigated, in the presence of amplified spontaneous emission noise, scintillation, beam spreading, atmospheric attenuation and interchannel crosstalk. Using on-off keying modulation, Monte Carlo simulation techniques are used to obtain the average bit error rate and system capability due to scintillation and the effect of introducing a power control algorithm (PCA) to the system is investigated. The PCA ensures that at any receiving instant, the same turbulence- free powers are received by all the receiving lenses. The performance of various WDM FSO communication system configurations such as non-amplified systems with an adaptive decision threshold (NOAADT), non- amplified systems with a non-adaptive decision threshold, fixed gain amplified systems with an adaptive decision threshold, fixed gain amplified systems with a non- adaptive decision threshold and saturated gain amplified systems with a non-adaptive decision threshold (SOA- NADT) are investigated. Results obtained show that the SOANADT is superior to the NOAADT and the PCA is only beneficial in amplified systems. 展开更多
关键词 WAVELENGTH-DIVISION multiplexing (WDM) FREE-SPACE OPTICAL (FSO) communication CROSSTALK OPTICAL amplifier (OA) gain SATURATION decision threshold
Analysis on multiple optical line terminal passive optical network based open access network
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作者 Love KUMAR Amarpal SINGH Vishal SHARMA 《中国光电子学前沿:英文版》 EI CSCD 2019年第2期208-214,共7页
Passive optical networks (PONs) offer suffi-cient bandwidth to transfer huge amount having different packet sizes and data rates being generated by fusion of various networks. Additionally, multiple optical line termi... Passive optical networks (PONs) offer suffi-cient bandwidth to transfer huge amount having different packet sizes and data rates being generated by fusion of various networks. Additionally, multiple optical line terminals (OLTs) PONs reduce the computational com-plexity of data processing for nonuniform traffic. However, in order to improve the bandwidth allocation efficiency of a mixture of service providers, dynamic bandwidth algo-rithm (DBA) is needed for uplink communication. In this paper, a PON based open access network (OAN) is analyzed for bi-directional communication at various data rates. Multiple wavelengths are used to modulate the data of various service providers to evade the complicated DBA for uplink data broadcasting. The performance of the network is reported in terms of bandwidth exploitation, uplink effectiveness, overhead-to-data ratio and time cycle duration. The network is analyzed at various data rates to reveal the data accommodation capacity. 展开更多
关键词 PASSIVE OPTICAL NETWORK (PON) open access NETWORK (OAN) OPTICAL line terminal (OLT) hybrid NETWORK
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