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Influence of tungsten particle size on microstructure and mechanical properties of high strength and tough tungsten particle-reinforced nickel-based composites by laser-direct energy deposition

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Journal of Materials Science & Technology 2024年第5期172卷 213-227页

作者： Wenji Song Dengzhi Wang Congwen Tang Pengfei Sun Jiaxing Yang Zhidong Xu Tao Lai Jianqiang Gong Qianwu Hu Xiaoyan Zeng Wuhan National laboratory for optoelectronics Huazhong University of Science and TechnologyWuhan 430000China

Tungsten(W)particle-reinforced nickel(Ni)-based composites were fabricated via laser-direct energy de-position(L-DED).The influence of the W particle size on the microstructure and mechanical properties of the deposited samples was systematically *** results indicate that refining the W particle size could refine theγ-Ni grains and subgrains,thin the(Ni,Cr)_(4)W interface layer,and increase the disloca-tion density of the intergranular matrix,thus improving the tensile strength and elongation of the L-DED *** W particle size decreased from 75 to 150μm to 6.5-12μm,the tensile strength and elonga-tion of the deposited samples increased by 150 MPa and 2.9 times to 1347.6±15.7 MPa and 17.5±0.4%,*** on the properties of the interface(Ni,Cr)_(4)W,a load-transfer efficiency factor suitable for this composite was proposed and the load-transfer strengthening formula was optimized.A quanti-tative analysis of the strengthening mechanisms was established considering load-transfer strengthening,Hall-Petch strengthening,thermal-mismatch strengthening,and solid-solution *** calcu-lated contribution of each strengthening mechanism to the yield strength and theoretical calculations were in good agreement with the experimental *** article breaks the bottleneck of poor plasticity of W particle-reinforced Ni-based composites prepared by L-DED and provides a theoretical basis for the construction design of W particle-reinforced Ni-based composites with excellent mechanical properties.

关键词： Laser-direct energy deposition(L-DED) Tungsten particle reinforcements Mechanical property Strengthening mechanism

LP modes exchange based on multiplane light conversion

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Chinese Optics Letters 2024年第3期22卷 14-18页

作者：钟亚楠林楚璇方浚丞雷霆袁小聪 Nanophotonics research Centre Shenzhen Key Laboratory of Micro-Scale Optical Information Technology&Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China

Data exchange between different mode channels is essential in the optical communication network with mode-division multiplexing(MDM).However,there are challenges in realizing mode exchange with low insert loss,low mode crosstalk,and high ***,we designed and fabricated a mode exchange device based on multiplane light conversion(MPLC),which supports the transmission of LP01,LP11a,LP11b,and LP21 modes in the C-band and *** simulated exchanged mode purities are greater than 85%.The phase masks were fabricated on a silicon substrate to facilitate the integration with optical systems,with an insert loss of less than 2.2 dB and mode crosstalk below-21 dB due primarily to machining inaccuracies and alignment *** carried out an optical communication experiment with 10 Gbit/s OOK and QPSK data transmission at the wavelength of 1550 nm and obtained excellent performance with the *** paves the way for flexible data exchange as a building block in MDM optical communication networks.

关键词： mode exchange mode-division multiplexing multiplane light conversion

980 nm Near-Infrared Light-Emitting Diode Using All-Inorganic Perovskite Nanocrystals Doped with Ytterbium Ions

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Tsinghua Science and Technology 2024年第1期29卷 207-215页

作者： Zhenglan Ye Taoran Liu Dan Chen Yazhou Yang Jiayi Li Yaqing Pang Xiangquan Liu Yuhua Zuo Jun Zheng Zhi Liu Buwen Cheng State Key laboratory on Integrated optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Intelligent Network research Institute Zhejiang LabHangzhou 311100China

All-inorganic perovskite(CsPbX3)nanocrystals(NCs)have recently been widely investigated as versatile solution-processable light-emitting *** to its wide-bandgap nature,the all-inorganic perovskite NC Light-Emitting Diode(LED)is limited to the visible region(400-700 nm).A particularly difficult challenge lies in the practical application of perovskite NCs in the infrared-spectrum *** this work,a 980 nm NIR all-inorganic perovskite NC LED is demonstrated,which is based on an efficient energy transfer from wide-bandgap materials(CsPbCl3 NCs)to ytterbium ions(Yb3+)as an NIR emitter doped in perovskite *** optimized CsPbCl3 NC with 15 mol%Yb3+doping concentration has the strongest 980 nm photoluminescence(PL)peak,with a PL quantum yield of 63%.An inverted perovskite NC LED is fabricated with the structure of ITO/PEDOT:PSS/poly-TPD/CsPbCl3:15 mol%Yb3+NCs/TPBi/LiF/*** LED has an External Quantum Efficiency(EQE)of 0.2%,a Full Width at Half Maximum(FWHM)of 47 nm,and a maximum luminescence of 182 cd/m?.The introduction of Yb3+doping in perovskite NCs makes it possible to expand its working wavelength to near-infrared band for next-generation light sources and shows potential applications for optoelectronic integration.

关键词： perovskite nanocrystals rare-earth doping Light-Emitting Diode(LED) near-infrared optical interconnection

Achieving full mutualism with massive passive devices for multiuser MIMO symbiotic radio

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Science China(Information Sciences) 2024年第9期67卷 196-212页

作者： Jingran XU Zhuoyin DAI Yong ZENG Shi JIN Tao JIANG National Mobile Communications research laboratory Southeast University Purple Mountain Laboratories research Center of 6G Mobile Communications School of Cyber Science and Engineering and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Symbiotic radio(SR) is one of the attractive communication technologies to facilitate largescale Internet of Things(IoT) connections with enhanced energy and spectrum efficiency, where passive backscatter devices(BDs) modulate their information over the radio frequency(RF) signals emitted by the active primary transmitters(PTs). Meanwhile, the primary transmission can be strengthened with the additional multipaths created by BDs. To capitalize to a greater extent on the mutualism relationship between the two types of communication, this paper studies multiple-input multiple-output(MIMO) SR communication systems including multiple PTs and massive BDs. We derive the achievable rate expressions of each PT and BD, as well as the sum rate expressions of primary and secondary communication, *** asymptotic analysis is given to derive the active and passive communication rates with a large number of BDs. Furthermore, for the general case with a finite number of BDs, we study the precoding optimization problem to maximize the sum rate of primary communication, while ensuring that the sum rate of secondary communication and the individual rate for each PT and BD in the prescribed active and passive user sets satisfy the specified thresholds. Simulation results are presented to verify the analytical studies.

关键词： multiuser MIMO SR backscattering massive backscatter devices asymptotic analysis active and passive communication

Transient long-range distance measurement by a Vernier spectral interferometry

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Photonics research 2024年第6期12卷 1107-1114页

作者： LIANG XU KUN WANG CHEN LIU WENYING CHEN CHI ZHANG XINLIANG ZHANG Wuhan National laboratory for optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley laboratory Wuhan 430074China

Rapid and long-range distance measurements are essential in various industrial and scientific applications,and among them,the dual-comb ranging system attracts great attention due to its high ***,the tem-poral asynchronous sampling results in the tradeoff between frame rate and ranging precision,and the non-ambiguity range(NAR)is also limited by the comb cycle,which hinders the further advancement of the dual-comb ranging *** this constraint,we introduce a Vernier spectral interferometry to improve the frame rate and NAR of the ranging ***,leveraging the dispersive time-stretch technology,the dual-comb interferometry becomes spectral ***,the asynchronous time step is unlimited,and the frame rate is improved to 100 ***,dual-wavelength bands are introduced to implement a Vernier spectral interferometry,whose NAR is enlarged from 1.5 m to 1.5 ***,this fast and long-range system also demonstrated high precision,with a 22.91-nm Allan deviation over 10-ms averaging *** a result,the proposed Vernier spectral interferometry ranging system is promising for diverse applications that necessitate rapid and extensive distance measurement.

关键词： interferometry spectral system

A continuous-wave Nd:YVO_(4)-KGW intracavity Raman laser with over 34% diode-to-Stokes optical efficiency

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High Power Laser Science and Engineering 2024年第2期12卷 62-68页

作者： Quan Sheng Jingni Geng Tianchang Liu Shijie Fu Wei Shi Jianquan Yao Institute of Laser and optoelectronics School of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjinChina Key laboratory of Optoelectronic Information Technology(Ministry of Education) Tianjin UniversityTianjinChina

We demonstrate a continuous-wave(CW)Nd:YVO_(4)-potassium gadolinium tungstate(KGW)intracavity Raman laser with a diode-to-Stokes optical efficiency of 34.2%.By optimizing the cavity arrangement and reducing the cavity losses,8.47 W Stokes output at 1177 nm was obtained under an incident 878.6 nm diode pump power of 24.8 *** influence of cavity losses on the power and efficiency of the CW Raman laser,as well as the potential for further optimization,was investigated based on the numerical *** observation of thermally-induced output rollover was well explained by the calculation of the thermal lensing and cavity stability,indicating that the end-face curvature played an important role when the end-face of the crystal was highly reflective coated to make the cavity.A 10.9 W Stokes output under 40.9 W incident pump was also demonstrated with a cavity arrangement less sensitive to the end-face curvature,which is the highest output power of CW intracavity Raman lasers reported.

关键词： continuous wave intracavity Raman laser KGW crystal thermal lens

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On-chip stimulated Brillouin scattering[Invited]

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Chinese Optics Letters 2024年第2期22卷 28-41页

作者：余林峰黄楚坤程铭王康石浩天黄强孙军强 Wuhan National laboratory for optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

On-chip stimulated Brillouin scattering(SBS)has attracted extensive attention by introducing acousto-optic coupling interactions in all-optical signal processing systems.A series of chip-level applications such as Brillouin lasers,amplifiers,gyroscopes,filters,and nonreciprocal devices are realized based on Brillouin acousto-optic ***,we first introduce the fundamental principle of SBS in integrated photonics and a method for calculating Brillouin gain;then we illustrate the Brillouin effect on different material platforms with diverse ***,we make a concise conclusion and offer prospects on the future developments of on-chip SBS.

关键词： stimulated Brillouin scattering integrated photonics silicon-on-insulator

Mode-insensitive and mode-selective optical switch based on asymmetric Y-junctions and MMI couplers

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Photonics research 2024年第3期12卷 423-430页

作者： SHIJIE SUN QIDONG YU YUANHUA CHE TIANHANG LIAN YUHANG XIE DAMING ZHANG XIBIN WANG State Key laboratory of Integrated optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Driven by the large volume demands of data in transmission systems,the number of spatial modes supported by mode-division multiplexing(MDM)systems is being increased to take full advantage of the parallelism of the signals in different spatial *** a key element for photonic integrated circuits,the multimode waveguide optical switch(MWOS)is playing an important role for data exchange and signal ***,the function of the traditional MWOS is simple,which could only implement the mode-insensitive or mode-selective switching function;it is also difficult to scale to accommodate more spatial modes because of the limitation of the device ***,it is still challenging to realize a multifunctional and scalable MWOS that could support multiple modes with low power consumption and high ***,we propose and experimentally demonstrate a multifunctional MWOS based on asymmetric Y-junctions and multimode interference(MMI)couplers fabricated on a polymer waveguide *** mode-insensitive and mode-selective switching functions can be achieved via selectively heating different electrode *** fabricated device with the total length of∼0.8 cmshows an insertion loss of less than 12.1 dB,and an extinction ratio of larger than 8.4 dB with a power consumption of∼32 mW for both mode-insensitive and mode-selective switching functions,at 1550 nm *** proposed MWOS can also be scaled to accommodate more spatial modes flexibly and easily,which can serve as an important building block for MDM systems.

关键词： waveguide optical mode

Nano-effect enhanced cooperative luminescence of Yb^(3+) clusters in bulk materials

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Journal of Rare Earths 2024年第3期42卷 473-478,I0002页

作者： Daguang Li Jiahao Cui Yanhui Dong Hao Cui Dan Zhao Weiping Qin State Key laboratory on Integrated optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun130012China

In order to improve the multi-ion cooperative transition, we proposed and exploited a novel nanoscale effect, namely the nanoshell effect in bulk materials. Based on the effect, an optimal material structure was designed by coating the surfaces of Ca F_(2):Yb^(3+)micron size particles with ZrO_(2). An about 2 times higher intensity of cooperative luminescence is observed upon laser excitation at 980 nm. Dynamical analysis exhibits that the novel effect plays a key role in improving the performance of cooperative transitions. Our results also suggest that the nanoshell effect in bulk materials is likely to be significant in some special cases, which have not been reported yet in the literature.

关键词： Yb^(3+)cluster ZrO_(2) Nanoshell Enhancement Cooperative luminescence Rare earths