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Mineralogy of Manganese Oxide Minerals in Iron Manganese Nodules of Several Main Soils in China 被引量:7
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作者 TAN WENFENG LIU FAN +2 位作者 LI YONGHUA HE JIZHENG LI XUEYUAN 《Pedosphere》 SCIE CAS CSCD 2000年第3期265-274,共10页
X-ray diffraction and selective chemical dissolution methods were used to investigate the composition of Mn oxide minerals in Fe-Mn nodules of several main types of soils in China. The changes of relative intensity of... X-ray diffraction and selective chemical dissolution methods were used to investigate the composition of Mn oxide minerals in Fe-Mn nodules of several main types of soils in China. The changes of relative intensity of X-ray diffraction patterns were studied both before and after chemically selective dissolution. It was found that lithiophorite was a common Mn oxide in all examined Fe-Mn nodules. Todorokite, however, was a predominant Mn oxide in Fe-Mn nodules in caf-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn nodules of arp-udic Luvisols in Wuhan and Zaoyang, Hubei Province, contained birnessite and vernadite. Hollandite was found in Fe-Mn nodules of alt-udic Ferrisols of Yizhang, Hunan Province; arp-udic Luvisols of Zaoyang, Hubei Province; and cal-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn nodules in alt-udic Ferrisols of Guiyang, Hunan Province, had a few coronadites. Mineralogy of Mn oxide minerals in soil Fe-Mn nodules was related to soil environment, soil types and quantities of relevant cations. 展开更多
关键词 Fe-Mn nodule Mn oxide minerals soil X-ray difraction
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{112}<111>Twins or Twinned Variants Induced by Martensitic Transformation?
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作者 Zuohua Wang Haidong Sun +4 位作者 Peng Wang Ning Liu Pinwen Zhu Dongli Yu Hongwang Zhang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2023年第1期133-140,共8页
Twinned substructure in lath martensite was induced in the interstitial free(IF)steel via a high pressure thermal cycle(heating up to 1100℃and holding for 30 min,cooling at 10℃/s to room temperature under a pressure... Twinned substructure in lath martensite was induced in the interstitial free(IF)steel via a high pressure thermal cycle(heating up to 1100℃and holding for 30 min,cooling at 10℃/s to room temperature under a pressure of 4 GPa).Experimental observations and theoretical simulation confrm that the twinned substructure has the origin related to the twinned variants rather than the bcc{112}<111>twins,while extra difraction spots were caused by crystal overlapping rather than any extra phase.The diferences in crystallography and electron difraction behavior between twinned variants and{112}<111>twins were discussed in detail. 展开更多
关键词 Twinned variants {112}<111>twins Martensitic transformation Crystal overlapping Electron difraction
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Study of laser beam scattering by inhomogeneous ensemble of red blood cells in a shear flow
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作者 S.Yu Nikitin A.E.Lugovtsov +2 位作者 V.D.Ustinov M.D.Lin A.V.Priezzhev 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2015年第4期85-96,共12页
Laser elktacytometry is a technique widely used for measuring the deformability of red blood cells(erythrocytes)in blood samples in vitro.In ektacytometer,a flow of highly diluted suspension of erythrocytes in variabl... Laser elktacytometry is a technique widely used for measuring the deformability of red blood cells(erythrocytes)in blood samples in vitro.In ektacytometer,a flow of highly diluted suspension of erythrocytes in variable shear stress conditions is iluninated with a laser beam to obtain a diffraction pattern.The diffraction pattern provides information about the shapes(shear induced elongations)of the cells under investigation.This paper is dedicated to developing the technique of laser ektacytometry s0 that it would enable one to measure the distrilbution of the erythrocytes in deformability.We discuss the problem of calibration of laser elktacytometer and test a novel data processing algorithm allowing to determine the parameters of the distribution of ery-throcytes deformability.Experimentally,we examined 12 specimens of blood of rats under the action of 4 shear stresses.Analysis of the data shows that in conditions of a limited range of digitizing the diffraction patterns,the measurement errors for the mean deformability,deform-ability scatter and the skewness of erythrocytes distribution in deformability by our method are respectively 15%,20%and 20%. 展开更多
关键词 Laser ifractometry ektacytometry shear flow difraction pattern deformability of erythrocytes erythrocytes variance in shapes image analysis
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FERROELECTRIC AND MAGNETIC PROPERTIES OF PEROVSKITE STRUCTURED Bi_(1-x-y)Gd_(x)Ba_(y)Fe_(1-y)Ti_(y)O_(3)MAGNETOELECTRIC CERAMICS
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作者 RADHESHYAM RAI IGOR BDIKIN +1 位作者 M.A.VALENTE ANDREI L.KHOLKIN 《Journal of Advanced Dielectrics》 CAS 2011年第2期257-267,共11页
Ternary solid solutions of BiFeO_(3),GdFeO_(3)and BaTiO_(3)have been prepared by solid-state reaction method.Dielectric properties of these ceramics have been characterized in the tem-perature range between room tempe... Ternary solid solutions of BiFeO_(3),GdFeO_(3)and BaTiO_(3)have been prepared by solid-state reaction method.Dielectric properties of these ceramics have been characterized in the tem-perature range between room temperature and 673 K and magnetic properties between 5 K and 300K.For the understanding of the multiferroic property,the relation between the crystal structures,magnetic transition and ferroelectric transitions with increasing temperature have been analyzed.All ceramic samples show single perovskite phase.When Ba content exceeds 0.2 wt%,the sintering ability is weakened and the phase structure of Bi_(1-x-y)Gd_(x)Ba_(y)Fe_(1-y)Ti_(y)O_(3)(with x=0.2 and y=0.1,0.2,0.3,0.4,0.5)solid solution changes from rhombohedral to tetragonal phase.The maximum ferroelectric transition temperature(T_(c))of this system was in the range 154-165℃with the dielectric constant peak of 6000 for y=0.5 at 100 kHz.Well-saturated piezoresponse hysteresis loops were observed for all compositions indicating room temperature ferroelectricity.With increasing Ba content(up to 0.3 wt%)the remanent magnetization M,increased and the coercive magnetic field decreased. 展开更多
关键词 CERAMICS X-ray difraction dielectric properties electrical properties magnetic properties
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Effect of neodymium doping on structural,microscopic and electrical properties of barium phosphate system
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作者 Shivani Suri Vishal Singh K.K.Bamzai 《Journal of Advanced Dielectrics》 CAS 2014年第2期1-10,共10页
Neodymium-doped barium phosphate(NdBP)was prepared as single crystal by room temperature solution technique known as gel encapsulation technique.Single crystal X-ray diffraction shows that the crystal belongs to ortho... Neodymium-doped barium phosphate(NdBP)was prepared as single crystal by room temperature solution technique known as gel encapsulation technique.Single crystal X-ray diffraction shows that the crystal belongs to orthorthombic system.The flower type morphology was observed by scanning electron microscope(SEM)and the stoichiometric composition of the prepared crystal was observed by energy dispersive X-ray analysis(EDAX).The presence of functional group and other groups was studied by Fourier transform infrared spectroscopy(FTIR).The electrical properties of these materials like dielectric constant(ε′),dieletric loss(tan σ)and ac conductivity[ln(σac)]was studied at different temperatures ranging from 40℃ to 420℃ in the frequency range of 5 kHz to 1 MHz.The activation energy values decreases with increase in frequency suggesting that the conduction mechanism is because of hopping of charge carriers. 展开更多
关键词 Inorganic compounds crystal growth X-ray difraction dielectric properties
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氧化钨氢还原过程中的物相转变 被引量:16
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作者 陈绍衣 钱崇梁 《中南工业大学学报》 CSCD 1995年第5期605-609,共5页
仲钨酸铵(APT)在不同温度与不同气氛下热分解和(或)氢还原制得了4种典型的氧化钨,采用X射线衍射分析研究了这些氧化钨在氢还原过程中的物相转变,试验结果表明:APT的分解条件和氧化钨的氢还原工艺对钨粉生产都是很重要的... 仲钨酸铵(APT)在不同温度与不同气氛下热分解和(或)氢还原制得了4种典型的氧化钨,采用X射线衍射分析研究了这些氧化钨在氢还原过程中的物相转变,试验结果表明:APT的分解条件和氧化钨的氢还原工艺对钨粉生产都是很重要的.本文为氧化钨和钨粉生产厂提供了某些图谱、数据和推论;特别是用干燥氢还原W18O49直接生成β-W和α-W可避免中间的WO2形成,这一新发现,对高效生产细钨粉有重要意义。 展开更多
关键词 氧化钨 分解 氢还原 X射线衍射分析 物相转变
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简易荧光仪共振光散射光谱法测定蛋白质的研究 被引量:8
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作者 王林 王照丽 李树伟 《化学研究与应用》 CAS CSCD 北大核心 2001年第5期591-593,共3页
The article studied the resonance light scattering of protein red alizarin with the simple fluorescence spectrophotometer first.In Britton Robinson butter of 4.10,the red alizarin combined with proteins by intermolecu... The article studied the resonance light scattering of protein red alizarin with the simple fluorescence spectrophotometer first.In Britton Robinson butter of 4.10,the red alizarin combined with proteins by intermolecular forces to form complexes,causing an enhance of resonance light scattering(RLS) at maximum wavelength of about 360nm.Based on the enhancement of resonance light scattering a novel method for the determination of proteins using red alizarin was developed.Though it affected by the limit of the filter of spectrophotometer the experiment used the wavelength of incident light doesn’t lie in the maximum wavelength,the method has better linear range within 0~10.0μg/ml,determination limits being 0.04μg/ml.The method had been used to determine total proteins in human serum samples and with accuracy and torelant to many foreign substance. 展开更多
关键词 蛋白质 茜素红 共振光散射光谱 测定 荧光分光光度计 分析
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单级衍射量子点阵光栅的聚焦离子束直写法制备及光学性能检测 被引量:6
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作者 黄成龙 张继成 +4 位作者 刁凯迪 曾勇 易勇 曹磊峰 王红斌 《物理学报》 SCIE EI CAS CSCD 北大核心 2014年第1期332-336,共5页
采用聚焦离子束直写技术,成功制作了面积为200μm×200μm,线密度500 mm 1,圆孔直径800 nm,金吸收体厚度为500 nm的单级衍射量子点阵光栅.研究了该光栅在波长442 nm激光下不同传输距离的衍射特性以及相对衍射效率.实验结果表明,量... 采用聚焦离子束直写技术,成功制作了面积为200μm×200μm,线密度500 mm 1,圆孔直径800 nm,金吸收体厚度为500 nm的单级衍射量子点阵光栅.研究了该光栅在波长442 nm激光下不同传输距离的衍射特性以及相对衍射效率.实验结果表明,量子点阵光栅不存在高级衍射,只保留了±1级和0级衍射,具有良好的单级衍射特性.1级衍射与0级衍射间距随传输距离的增大而增大,实测值与理论计算值相符. 展开更多
关键词 聚焦离子束直写加工(FIB) 量子点阵光栅(QDADG) 单级衍射
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碱激发锰渣胶凝材料的探索研究 被引量:6
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作者 宋旭艳 韩静云 +2 位作者 郜志海 杨末丽 盛广宏 《材料导报》 EI CAS CSCD 北大核心 2009年第22期70-73,共4页
以锰渣为主要研究对象,采用X射线衍射分析、差热分析等测定方法对原材料进行了物性分析,锰渣的主要矿物组成有SiO2和CaO,属于碱性废渣,当温度低于550℃时其热稳定性较好。通过对复合碱激发剂的探索可知,当水玻璃模数为1.6时,25%水玻璃、... 以锰渣为主要研究对象,采用X射线衍射分析、差热分析等测定方法对原材料进行了物性分析,锰渣的主要矿物组成有SiO2和CaO,属于碱性废渣,当温度低于550℃时其热稳定性较好。通过对复合碱激发剂的探索可知,当水玻璃模数为1.6时,25%水玻璃、2.5%NaOH和1%K2CO3复合激发锰渣后,其碱胶凝材料的凝结时间满足浆体的一般工作要求。在该复合激发剂作用下,以10%硅酸盐水泥熟料等量替代锰渣后,制成的碱激发锰渣胶凝材料的力学强度发展符合胶凝材料的一般规律;其水化过程分析表明,随水化龄期的延长,SiO2被剥蚀解体量增多,生成较多的C-S-H凝胶及少量沸石类结构复杂的物质,强度逐渐提高。 展开更多
关键词 锰渣 碱激发 X射线衍射分析 差热分析 力学强度 水化过程
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化学活化烟气灰的活性评价及火山灰效应研究 被引量:2
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作者 宋旭艳 韩静云 郜志海 《材料导报》 EI CAS CSCD 北大核心 2010年第16期76-79,共4页
以常州武进烟气灰为主要研究对象,采用有机激发剂三乙醇胺和复合型激发剂FAA对其进行活性激发,分析化学活化烟气灰的火山灰效应,结果表明,激发剂可明显提高烟气灰的活性,其中三乙醇胺不但具有明显的早强作用,对体系后期强度的发展也有... 以常州武进烟气灰为主要研究对象,采用有机激发剂三乙醇胺和复合型激发剂FAA对其进行活性激发,分析化学活化烟气灰的火山灰效应,结果表明,激发剂可明显提高烟气灰的活性,其中三乙醇胺不但具有明显的早强作用,对体系后期强度的发展也有一定贡献。采用Ca(OH)2剩余量测定、X射线衍射分析等方法评定烟气灰的活性,结果表明,激发剂的引入可显著降低活性评定体系中的Ca(OH)2剩余量,其中在三乙醇胺激发下,Ca(OH)2剩余量较少;在激发剂的作用下,活性评定体系中的Ca(OH)2峰值明显下降,烟气灰对Ca(OH)2的消耗明显增加,其中在三乙醇胺作用下体系中的Ca(OH)2峰值较低,表明三乙醇胺对烟气灰的激发效果较FAA好。 展开更多
关键词 烟气灰 化学活化 火山灰效应 活性评定 CA(OH)2 X射线衍射分析
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基于金属圆柱阵列的原子光学晶格 被引量:1
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作者 胡欣智 葛秉炎 +3 位作者 王正岭 童唯扬 刘啸 聂之峰 《电子科技》 2018年第1期42-45,49,共5页
文中提出一种采用金属圆柱阵列实现二维原子光学晶格的方案,并利用Comsol软件仿真对其表面等离激元特性和三维光强分布进行研究。在此基础上分析冷原子所受光学势与范德瓦尔斯势的作用,讨论了总势场分布及势阱中心位置与结构参数的依赖... 文中提出一种采用金属圆柱阵列实现二维原子光学晶格的方案,并利用Comsol软件仿真对其表面等离激元特性和三维光强分布进行研究。在此基础上分析冷原子所受光学势与范德瓦尔斯势的作用,讨论了总势场分布及势阱中心位置与结构参数的依赖关系。研究发现,在4个金属纳米圆柱中间上方可以形成长350 nm、宽350 nm、高66 nm的周期性暗中空区域并可用于冷原子囚禁。该研究结果为获得突破衍射极限的原子光学周期性元器件提供了一个新的思路。 展开更多
关键词 金属圆柱阵列 表面等离激元 原子光学晶格 衍射极限
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利用改进的两维FFT算法设计的费涅耳型Kinoform
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作者 朱泽钦 齐开国 +1 位作者 姚焜 李银妹 《量子电子学报》 CAS CSCD 北大核心 2001年第6期493-498,共6页
利用对称性进了两维快速傅里叶变换(FFT),以这种改进的快速傅里叶变换模拟相干光的费涅耳衍射,设计出傅里叶型Kinoform和等效于透镜的 Kinoform合二为一的费涅耳型 Kinoform.从对称性的思路出发将一维... 利用对称性进了两维快速傅里叶变换(FFT),以这种改进的快速傅里叶变换模拟相干光的费涅耳衍射,设计出傅里叶型Kinoform和等效于透镜的 Kinoform合二为一的费涅耳型 Kinoform.从对称性的思路出发将一维快速傅里叶变换的对应项应用到两维快速傅里叶变换中,避免一般所采用的分别对矩阵的行和列做一维快速傅里叶变换的做法,观察到计算时间的明显缩短.将此改进的两维FFT算法应用于 Gerchberg-Saxten迭代算法[2],设计的 Kinoform的精度相对于文献[1]的结果提高了一个数量级.给出了Kinoform及其费涅耳衍射光强分布的计算机模拟结果. 展开更多
关键词 费涅耳衍射 KINOFORM 计算机模拟 迭代算法 两维快速傅里叶变换
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短波段光栅衍射效率计算软件设计
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作者 王淑红 《长春光学精密机械学院学报》 1997年第2期7-11,共5页
求文结合光栅电磁理论中的微分方法,采用具有较高稳定性和精确度的数值算法,编制了可用于计算短波段光谱范围的任意槽形光栅衍射效率分布特性的软件,其计算结果具有相当的准确性;该软件可从理论上分析入射角、糟深、闪耀角及光栅周... 求文结合光栅电磁理论中的微分方法,采用具有较高稳定性和精确度的数值算法,编制了可用于计算短波段光谱范围的任意槽形光栅衍射效率分布特性的软件,其计算结果具有相当的准确性;该软件可从理论上分析入射角、糟深、闪耀角及光栅周期对衍射效率的影响。 展开更多
关键词 光栅 衍射效率 软件 短波段
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Dielectric,electrical conduction and magnetic properties of multiferroic Bi_(0.8)Tb_(0.1)Ba_(0.1)Fe_(0.9)Ti_(0.1)O_(3)perovskite compound
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作者 Poonam Kumari Radheshyam Rai +1 位作者 Seema Sharma M.A.Valente 《Journal of Advanced Dielectrics》 CAS 2017年第5期47-56,共10页
This work focuses on the structural,electrical and magnetic properties of Bi_(0.8)Tb_(0.1)Ba_(0.1)Fe_(0.9)Ti_(0.1)O_(3)ceramics,fabricated by solid state reaction procedure.XRD forms of the samples at RT exhibited per... This work focuses on the structural,electrical and magnetic properties of Bi_(0.8)Tb_(0.1)Ba_(0.1)Fe_(0.9)Ti_(0.1)O_(3)ceramics,fabricated by solid state reaction procedure.XRD forms of the samples at RT exhibited perovskite phase through the hexagonal structure at room temperature.Dielectric studies of the materials with frequency at different temperatures(25-400℃)exhibit two dielectric anomalies,first at 175℃(ferroelectric-ferroelectric transition)and second at around 320℃(ferroelectric-paraelectric transition).The Curie temperature moved towards the low side temperature with the increase in frequency.The less value of activation energy got for these samples could be attributed to the influence of electronic contribution to the conductivity.A significant change in the magnetic studies was observed for Bi_(0.8)Tb_(0.1)Ba_(0.1)Fe_(0.9)Ti_(0.1)O_(3) ceramic.The impedance analysis confirms the non-Debye type nature of the ceramic and relaxation frequency moved to a higher temperature.The Nyquist plot and conductivity studies showed the NTCR behavior of samples.The highest magnetization field was found at temperature-268.15℃. 展开更多
关键词 Lead-free ceramics X-ray difraction(XRD) phase transitions electrical conduction magnetic properties MULTIFERROICS
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机械研磨烟气灰的活性评定过程研究
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作者 韩静云 宋旭艳 郜志海 《非金属矿》 CAS CSCD 北大核心 2010年第3期49-51,共3页
烟气灰是锰铁合金生产过程中排出的一种工业废渣。对烟气灰进行机械研磨,利于其潜在活性被激发,随着粉磨时间的增长,烟气灰的比表面积增大,活性激发效果较好,但粉磨时间过长,细度过细,则会降低烟气灰的活性。采用Ca(OH)2剩余量测定、X... 烟气灰是锰铁合金生产过程中排出的一种工业废渣。对烟气灰进行机械研磨,利于其潜在活性被激发,随着粉磨时间的增长,烟气灰的比表面积增大,活性激发效果较好,但粉磨时间过长,细度过细,则会降低烟气灰的活性。采用Ca(OH)2剩余量测定、X射线衍射分析等方法对机械研磨烟气灰的活性进行评定,结果表明:随粉磨时间的增长,烟气灰中晶体结晶度降低,活性评定体系中的Ca(OH)2剩余量减少,XRD图谱上Ca(OH)2峰值逐渐降低,但粉磨时间过长,由于微细粉体颗粒的团聚作用,导致体系中的Ca(OH)2剩余量较多,Ca(OH)2峰值反而较高,其中粉磨35min、即比表面积为765m2/kg的烟气灰的活性激发效果较好。 展开更多
关键词 烟气灰 机械研磨 活性评定 CA(OH)2 X 射线衍射分析
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Polarization and wavelength routers based on difractive neural network
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作者 Xiaohong Lin Yulan Fu +3 位作者 Kuo Zhang Xinping Zhang Shuai Feng Xiaoyong Hu 《Frontiers of Optoelectronics》 EI CSCD 2024年第3期17-28,共12页
In the feld of information processing,all-optical routers are signifcant for achieving high-speed,high-capacity signal processing and transmission.In this study,we developed three types of structurally simple and fexi... In the feld of information processing,all-optical routers are signifcant for achieving high-speed,high-capacity signal processing and transmission.In this study,we developed three types of structurally simple and fexible routers using the deep difractive neural network(D2 NN),capable of routing incident light based on wavelength and polarization.First,we implemented a polarization router for routing two orthogonally polarized light beams.The second type is the wavelength router that can route light with wavelengths of 1550,1300,and 1100 nm,demonstrating outstanding performance with insertion loss as low as 0.013 dB and an extinction ratio of up to 18.96 dB,while also maintaining excellent polarization preservation.The fnal router is the polarization-wavelength composite router,capable of routing six types of input light formed by pairwise combinations of three wavelengths(1550,1300,and 1100 nm)and two orthogonal linearly polarized lights,thereby enhancing the information processing capability of the device.These devices feature compact structures,maintaining high contrast while exhibiting low loss and passive characteristics,making them suitable for integration into future optical components.This study introduces new avenues and methodologies to enhance performance and broaden the applications of future optical information processing systems. 展开更多
关键词 Optical difractive neural network All-optical routers Polarization degree of freedom Wavelength degree of freedom
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