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High signal-to-noise ratio fiber laser at 1596 nm based on a Bi/Er/La co-doped silica fiber

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Chinese optics Letters 2022年第5期20卷 23-27页

作者：杨磊文建湘吴妍万英曾龙钊陈伟庞拂飞张小贝王廷云 laboratory of specialty Fiber optics and optical access networks School of Communication and Information Engineering Shanghai University

We fabricate a high-performance Bi/Er/La co-doped silica fiber with a fluorescence intensity of-33.8 d Bm and a gain coefficient of 1.9 d B/m. With the utilization of the fiber as a gain medium, a linear-cavity fiber laser has been constructed,which exhibits a signal-to-noise ratio of 74.9 d B at 1596 nm. It has been demonstrated that the fiber laser has a maximum output power of 107.4 m W, a slope efficiency of up to 17.0%, and a linewidth of less than 0.02 nm. Moreover, an all-fiber singlestage optical amplifier is built up for laser amplification, by which the amplified laser power is up to 410.0 m W with pump efficiency of 33.8%. The results indicate that the laser is capable of high signal-to-noise ratio and narrow linewidth,with potential applications for optical fiber sensing, biomedicine, precision measurement, and the pump source of the mid-infrared fiber lasers.

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Integration Technology of Micro-LED for Next-Generation Display

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Research 2023年第2期2023卷 389-413页

作者： Dingbo Chen Yu-Chang Chen Guang Zeng David WeiZhang Hong-Liang Lu State key laboratory of ASIC and System Shanghai lnstitute of Inteligent Electronics&SystemsSchoolof MicroelectronicsFudan UniversityShanghai 200433China Jia Shan Fudan Institute jaxingZhejang Province 314100China key laboratory of specialty Fiber optics and optical access networks Shanghai Institute Communication and Data ScienceShanghai UniversityShanghai 200444China

Inorganic micro light-emitting diodes(micro-LEDs)based on II-V compound semiconductors have been widely studied for self-emissive *** chips to applications,integration technology plays an indispensable role in micro-L... 详细信息

关键词： LED diodes LEDs

Piezoelectric transducer parameter selection for exciting a single mode from multiple modes of Lamb waves

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Chinese Physics B 2011年第9期20卷 262-270页

作者：张海燕于建波 School of Communication and Information Engineering Key Laboratory of Specialty Fiber Optics and Optical Access NetworksShanghai University

Excitation and propagation of Lamb waves by using rectangular and circular piezoelectric transducers surface- bonded to an isotropic plate are investigated in this work. Analytical stain wave solutions are derived for the two transducer shapes, giving the responses of these transducers in Lamb wave fields. The analytical study is supported by a numericM simulation using the finite element method. Symmetric and antisymmetric components in the wave propagation responses are inspected in detail with respect to test parameters such as the transducer geometry, the length and the excitation frequency. By placing only one piezoelectric transducer on the top or the bottom surface of the plate and weakening the strength of one mode while enhancing the strength of the other modes to find the centre frequency, with which the peak wave amplitude ratio between the SO and A0 modes is maximum, a single mode excitation from the multiple modes of the Lamb waves can be achieved approximately. Experimental data are presented to show the validity of the analyses. The results are used to optimize the Lamb wave detection system.

关键词： Lamb waves parameter selection analytical stain wave solutions single mode

A time reversal damage imaging method for structure health monitoring using Lamb waves

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Chinese Physics B 2010年第11期19卷 448-455页

作者：张海燕曹亚萍孙修立陈先华于建波 School of Communication and Information Engineering Key Laboratory of Specialty Fiber Optics and Optical Access NetworksShanghai University

This paper investigates the Lamb wave imaging method combining time reversal for health monitoring of a metallic plate structure. The temporal focusing effect of the time reversal Lamb waves is investigated theoretically. It demonstrates that the focusing effect is related to the frequency dependency of the time reversal operation. Numerical simulations are conducted to study the time reversal behaviour of Lamb wave modes under broadband and narrowband excitations. The results show that the reconstructed time reversed wave exhibits close similarity to the reversed narrowband tone burst signal validating the theoretical model. To enhance the similarity, the cycle number of the excited signal should be increased. Experiments combining finite element model are then conducted to study the imaging method in the presence of damage like hole in the plate structure. In this work, the time reversal technique is used for the recompression of Lamb wave signals. Damage imaging results with time reversal using broadband and narrowband excitations are compared to those without time reversal. It suggests that the narrowband excitation combined time reversal can locate and determine the size of structural damage more precisely, but the cycle number of the excited signal should be chosen reasonably.

关键词： Lamb wave time reversal damage imaging structure health monitoring

Experimental demonstration of 60 Gb/s optical OFDM transmissions at 1550 nm over 100 m OM1 MMF IMDD system with central launching

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Chinese optics Letters 2017年第6期15卷 32-35页

作者：陈健方玲张倩武张俊杰宋英雄李迎春汪敏 key laboratory of specialty Fiber optics and optical access networks Shanghai University Shanghai 200072 China

Record-high 60 Gb/s optical orthogonal frequency division multiplexing（OFDM） transmissions over intensity modulation and direct-detection（IMDD）-based 100 m optical mode（OM1） multi-mode fiber（MMF） links are experimentally demonstrated, utilizing 10 GHz electro-absorption modulated laser intensity modulators at a single 1550 nm wavelength. Adaptive bit loading and a simple central launching scheme of the proposed scheme show an effective way for combating the channel fading and simplifying the system structure. It shows good potential in short reach data center interconnections.

关键词： launching multiplexing demonstration fading modulated utilizing links transmitter offset patch

Theoretical and experimental analysis of second order Bragg resonance of 45° TFG and its fiber laser application

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Chinese optics Letters 2022年第1期20卷 122-126页

作者：宋青果叶柏林肖翔鹏黄成俊牟成博闫志君张琳 School of optical and Electronic Information NGIAHuazhong University of Science and TechnologyWuhan 430074China Shenzhen Techwinsemi Optoelectronic Co. Ltd.Shenzhen 518000China key laboratory of specialty Fiber optics and optical access networks Shanghai Institute for Advanced Communication and Data ScienceJoint International Research Laboratory of Specialty Fiber Optics and Advanced CommunicationShanghai UniversityShanghai 200444China Aston Institute of Photonic Technologies Aston UniversityBirmingham B47ETUK

We report the observation of second order Bragg resonance(2 nd-OBG) produced by tilted fiber gratings(TFGs) fabricated using phase mask UV *** theoretical analysis has revealed that the generation of high order Bragg resonance of gratings is induced by a square-shape refractive index profile,which is caused by over-saturated UV *** the experiment,we have studied the TFGs with different tilt angles under over-saturated UV exposure,in which all gratings have showed the 2 nd-OBR,and the larger tilt angle of the grating has the stronger 2 *** the tilt angle of the grating is-45°,the Bragg resonance exhibits very strong polarization dependence,because the 2 nd-OBR wavelength is located within the polarizing bandwidth of 45° ***,we have demonstrated an erbium-doped fiber laser with> 99.9% degree of polarization,and,by applying mechanical stretching on the grating,a wavelength tunable laser output has been *** output laser shows ~0.2 dB amplitude variation within 1 h continuous monitoring of the laser.

关键词： tilted fiber grating fiber laser

Novel scheme enabling broadcast signal transmission in WDM passive optical network

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Chinese optics Letters 2011年第4期9卷 14-17页

作者：马雪娇甘朝钦 key laboratory of specialty Fiber optics and optical access Shanghai University

We present a novel method for providing broadcast signal transmission in a wavelength division multiplexing passive optical network （WDM-PON）. An unmodulated optical carrier for downstream transmission and a pair of unmodulated single-side band subcarriers are utilized for broadcast delivery and upstream transmission, respectively. System performance at 2.5-Gb/s down/upstream and 2.5-Gb/s broadcast transmission is also investigated.

关键词： Carrier communication Fiber optic networks Light transmission Multiplexing equipment optical communication Wavelength division multiplexing

One-dimensional film-micro-cavity structure design for an asymmetrical interleaver filter

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光电子快报：英文版 2010年第2期6卷 85-88页

作者：于帅张娟 key laboratory of specialty Fiber optics and optical access networks Shanghai University

Based on the theory of one-dimensional photonic crystal,an asymmetrical interleaver filter composed of thin-film glass cavities is *** thin-film glass cavities are cascaded in the *** cavity is formed by evaporating several layers of reflecting films on two surfaces of the glass *** with other proposed structures,this interleaver filter is very simple and easy to realize,and it has flat passband and stopband.A design example of a 50 GHz interleaver filter with the duty cycle of 1:5 is *** influence of the structural parameters of each reflecting film(including the glass cavity) on the spectral performance is *** the design results with duty cycles of 1:3 and 1:4 are also shown and analyzed.

关键词：一维光子晶体结构设计交织器非对称微腔电影薄膜玻璃理论设计

Fabrication of optical fiber sensor based on double-layer SU-8 diaphragm and the partial discharge detection

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Optoelectronics Letters 2015年第1期11卷 61-64页

作者：商娅娜倪晴燕丁丁陈娜王廷云 key laboratory of specialty Fiber optics and optical access networks Shanghai University

In this paper, a partial discharge detection system is proposed using an optical fiber Fabry-Perot(FP) interferometric sensor, which is fabricated by photolithography. SU-8 photoresist is employed due to its low Young's modulus and potentially high sensitivity for ultrasound detection. The FP cavity is formed by coating the fiber end face with two layers of SU-8 so that the cavity can be controlled by the thickness of the middle layer of SU-8. Static pressure measurement experiments are done to estimate the sensing performance. The results show that the SU-8 based sensor has a sensitivity of 154.8 nm/kP a, which is much higher than that of silica based sensor under the same condition. Moreover, the sensor is demonstrated successfully to detect ultrasound from electrode discharge.

关键词：局部放电检测光纤传感器 SU-8 制造隔膜光致抗蚀剂二氧化硅基检测系统