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A High-Efficiency Broadband Superconducting Nanowire Single-Photon Detector with a Composite Optical Structure 被引量:1
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作者 顾敏 康琳 +6 位作者 张蜡宝 赵清源 郏涛 万超 徐睿莹 杨小忠 吴培亨 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第3期145-148,共4页
Superconducting nanowire single-photon detectors (SNSPDs) with a composite optical structure composed of phase-grating and optical cavity structures are designed to enhance both the system detection efficiency and t... Superconducting nanowire single-photon detectors (SNSPDs) with a composite optical structure composed of phase-grating and optical cavity structures are designed to enhance both the system detection efficiency and the response bandwidth. Numerical simulation by the finite-difference time-domain method shows that the photon absorption capacity of SNSPDs with a composite optical structure can be enhanced significantly by adjusting the parameters of the phase-grating and optical cavity structures at multiple frequency bands. The absorption capacity of the superconducting nanowires reaches 70%, 72%, 60.73%, 61.7%, 41.2%, and 46.5% at wavelengths of 684, 850, 732, 924, 1256, and 1426nm, respectively. The use of a composite optical structure reduces the total filling factor of superconducting nanowires to only 0.25, decreases the kinetic inductance of SNSPDs, and improves the count rates. 展开更多
关键词 LENGTH A High-Efficiency Broadband Superconducting Nanowire Single-Photon Detector with a Composite optical structure
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Woofer–tweeter adaptive optical structured illumination microscopy 被引量:3
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作者 QINGGELE LI MARC REINIG +4 位作者 DAICH KAMIYAMA BO HUANG XIAODONG TAO ALEX BARDALES JOEL KUBBY 《Photonics Research》 SCIE EI 2017年第4期329-334,共6页
A woofer–tweeter adaptive optical structured illumination microscope(AOSIM) is presented. By combining a low-spatial-frequency large-stroke deformable mirror(woofer) with a high-spatial-frequency low-stroke deformabl... A woofer–tweeter adaptive optical structured illumination microscope(AOSIM) is presented. By combining a low-spatial-frequency large-stroke deformable mirror(woofer) with a high-spatial-frequency low-stroke deformable mirror(tweeter), we are able to remove both large-amplitude and high-order aberrations. In addition, using the structured illumination method, as compared to widefield microscopy, the AOSIM can accomplish highresolution imaging and possesses better sectioning capability. The AOSIM was tested by correcting a large aberration from a trial lens in the conjugate plane of the microscope objective aperture. The experimental results show that the AOSIM has a point spread function with an FWHM that is 140 nm wide(using a water immersion objective lens with NA=1.1) after correcting a large aberration(5.9 μm peak-to-valley wavefront error with 2.05 μm RMS aberration). After structured light illumination is applied, the results show that we are able to resolve two beads that are separated by 145 nm, 1.62× below the diffraction limit of 235 nm. Furthermore, we demonstrate the application of the AOSIM in the field of bioimaging. The sample under investigation was a green-fluorescentprotein-labeled Drosophila embryo. The aberrations from the refractive index mismatch between the microscope objective, the immersion fluid, the cover slip, and the sample itself are well corrected. Using AOSIM we were able to increase the SNR for our Drosophila embryo sample by 5×. 展开更多
关键词 AO SIM WOOFER tweeter adaptive optical structured illumination microscopy
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Impact of Surface Passivation on the Electronic Structure and Optical Properties of the Si1-xGex Nanowires 被引量:1
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作者 赖信 张析 +1 位作者 张依兮 向钢 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期119-122,共4页
The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires (NWs) passivated with different functional groups (-H, -F and-OH) are investigated by using first-principles calculations. ... The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires (NWs) passivated with different functional groups (-H, -F and-OH) are investigated by using first-principles calculations. The results show that surface passivation influences the characteristics of electronic band structures significantly: the band gap widths and types (direct or indirect) of the Si1-xGe, NWs with different terminators show complex and robust variations, and the effective masses of the electrons in the NWs can be modulated dramatically by the terminators. The study of optical absorption shows that the main peaks of the parallel polarization component of Si1-x Gex NWs passivated with the functional groups exhibit prominent changes both in height and position, and are red-shifted with respect to those of corresponding pure Si NWs, indicating the importance of both the terminators and Ge concentrations. Our results demonstrate that the electronic and optical properties of Si1-xGex NWs can be tuned by utilizing selected functional groups as well as particular Ge concentrations for customizing purposes. 展开更多
关键词 110 OH x)Ge_x Nanowires Impact of Surface Passivation on the Electronic structure and optical Properties of the Si Ge
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Synthesis,Crystal Structure,and Optical Property of Zero-dimensional Quaternary Thioborate:Ba9B3GaS15 被引量:1
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作者 王金秋 刘鹏飞 +1 位作者 黎艳艳 吴立明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1860-1867,共8页
A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = ... A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = 22.266(2),c = 31.426(3) ?,V = 5931(2) ?~3,Z = 8,Mr = 1819.11,Dc = 4.075 g/cm3,μ = 13.684 mm^(-1),F(000) = 6320,S = 1.034,(Δρ)max = 5.039,(Δρ)min = –5.409 e/?~3,the final R = 0.0362 and w R = 0.1053 for 19243 observed reflections with I 〉 2σ(I). The structure is constructed by discrete [BS_3]^(3–) trigonal planes and isolated [GaS_4]^(5–) tetrahedra with Ba^(2+) and isolated S^(2–) filled among them. The UV-Vis-near-IR spectrum reveals a wide band gap of 3.15 eV that agrees with the electronic structure calculation. 展开更多
关键词 thioborate high-temperature solid-state reaction crystal structure optical band gap electronic structure calculation
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Dual-channel fiber-optic surface plasmon resonance sensor with cascaded coaxial dual-waveguide D-type structure and microsphere structure 被引量:1
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作者 李玲玲 魏勇 +4 位作者 刘春兰 任卓 周爱 刘志海 张羽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期201-208,共8页
To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-typ... To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-type structure and microsphere structure is proposed in this paper. The fiber sidepolishing technique converts the coaxial dual-waveguide fiber into a D-type one, and the evanescent wave in the ring core leaks, generating a D-type sensing region;the fiber optic fused ball push technology converts the coaxial dual waveguides into microspheres, and the stimulated cladding mode evanescent wave leaks, producing the microsphere sensing region. By injecting light into the coaxial dual-waveguide middle core alone, the sensor can realize single-stage sensing in the microsphere sensing area;it can also realize dual-channel sensing in the D-type sensing area and microsphere sensing area by injecting light into the ring core. The refractive index measurement ranges for the two channels are 1.333–1.365 and 1.375–1.405, respectively, with detection sensitivities of 981.56 nm/RIU and 4138 nm/RIU. The sensor combines wavelength division multiplexing and space division multiplexing technologies, presenting a novel research concept for multi-channel fiber SPR sensors. 展开更多
关键词 coaxial dual-waveguide optical fiber D structure optical fiber microsphere structure dual-channel fiber-optic surface plasmon resonance(SPR)sensor
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Optical and Structural Properties of In_(0.52)Al_(0.48)As/InP Structures Grown at Very High Arsenic Overpressures by Molecular Beam Epitaxy
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作者 S.F. Yoon(School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue,Singapore 639798, Rep. of Singapore 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1998年第3期231-235,共5页
Growth of ln0.52Al0.48As epitaxial layers on lnP(100) substrates by molecular beam epitaxy at a wide range of arsenic overpressures (V/III flux ratios from 30 to 300) has been carried out. Analysis performed using low... Growth of ln0.52Al0.48As epitaxial layers on lnP(100) substrates by molecular beam epitaxy at a wide range of arsenic overpressures (V/III flux ratios from 30 to 300) has been carried out. Analysis performed using low-temperature photoluminescence (PL) and double-axis X-ray diffraction (XRD) shows a strong and prominent dependence of the PL and XRD linewidths on the V/III flux ratio. Under our growth conditions, both the PL and XRD linewidths exhibit a minimum point at a V/III flux ratio of 150 which corresponds to a maximum in the PL intensity and XRD intensity ratio. Flux ratios exceeding 150 result in an increase in both the PL and XRD linewidths corresponding to a reduction in their associated intensities. Room temperature Raman scattering measurements show a narrowing in the lnAs-like and AlAs-like longitudinal-optic (LO)phonon linewidths which broaden at high flux ratios, while the LO phonon frequencies exhibit a gradual reduction as the flux ratio is increased. PL spectra taken at increasing temperatures show a quenching of the main emission peak followed by the evolution of a broad lower energy emission which is possibly associated with deep lying centres. This effect is more prominent in samples grown at lower V/III flux ratios. Hall effect measurements show a gradual reduction in the mobility in correspondence to an increase in the electron concentration as the flux ratio is increased. 展开更多
关键词 As/InP structures Grown at Very High Arsenic Overpressures by Molecular Beam Epitaxy INP optical and Structural Properties of In Al
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Helioal Structure and Optical Activity of Two New Derivatives of R(+)-1,1'-Binaphthyl-2,2'-diol
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作者 Ji Jun HUANG Bing DENG +1 位作者 and (Department of Chemistry, Shanxi University, Taiyuan 030006)Feng XUE Thomas C. W. MAK (Department of Chemistry, The Chinese University of Hong Kong,Shatin, New Territories, Hong Kong) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第12期0-0,0-0,共4页
Correlation between the belieal structure and optical activity of two derivatives of R(+)- 1, 1'-binaphthyl-2,2'-diol was derived from a study of their optical rotations, CD curves and Xray crystal structures.
关键词 BINAPHTHOL helical structure optical activity crystal structure
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Annealing behaviour of structure and morphology and its effects on the optical gain of Er^3+/yb^3+ co-doped Al2O3 planar waveguide amplifier
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作者 谭娜 张庆瑜 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2165-2169,共5页
Using transmission electron microscopy (TEM) and x-ray diffraction analysis, we have studied the structural and morphological evolution of highly Er/Yb co-doped A1203 films in the temperature range from 600℃-900℃.... Using transmission electron microscopy (TEM) and x-ray diffraction analysis, we have studied the structural and morphological evolution of highly Er/Yb co-doped A1203 films in the temperature range from 600℃-900℃. By comparison with TEM observation, the annealing behaviours of photoluminescence (PL) emission and optical loss were found to have relation to the structure and morphology. The increase of PL intensity and optical loss above 800℃ might result from the crystallization of amorphous Al2O3 films. Based on the study on the structure and morphology, a rate equation propagation model of a multilevel system was used to calculate the optical gains of Er-doped Al2O3 planar waveguide amplifiers involving the variation of PL efficiency and optical loss with annealing temperature. It was found that the amplifiers had an optimized optical gain at the temperature corresponding to the minimum of optical loss, rather than at the temperature corresponding to the maximum of PL efficiency, suggesting that the optical loss is a key factor for determining the optical gain of an Er-doped Al2O3 planar waveguide amplifier. 展开更多
关键词 Er-doped waveguide amplifier annealing behaviour structural characterization optical gain
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Band Structure and Optical Gain of InGaAs/GaAsBi Type-Ⅱ Quantum Wells Modeled by the k·p Model
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作者 Chang Wang Wenwu Pan +1 位作者 Konstantin Kolokolov Shumin Wang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期133-136,共4页
Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-con... Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k·p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain. 展开更多
关键词 As BI In Ga Band structure and optical Gain of InGaAs/GaAsBi Type Quantum Wells Modeled by the k p Model
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Electronic Structure and Optical Properties in Uranium Dioxide:the First Principle Calculations
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作者 隋鹏飞 戴振宏 +1 位作者 张晓玲 赵银昌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期129-133,共5页
We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe ... We report a study of the electronic structure and optical properties of uranium dioxide (U02) based on the ab-initio density-functional theory and using the generalized gradient approximation. To correctly describe the strong correlation between 5 f electrons of a uranium atom, we employ the on-site Hubbard U correction term and optimize the correlation parameter of the bulk uranium dioxide. Then we give the structural and electronic properties of the ground state of uranium dioxide. Based on the accurate electronic structure, we calculate the complex dielectric function of UO2 and the related optieM properties, such as reflectivity, refractive index, extinction index, energy loss spectra, and absorption coefficient. 展开更多
关键词 LDA GGA Electronic structure and optical Properties in Uranium Dioxide:the First Principle Calculations
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Studies on the Relationship between the Helical Structure and Optical Activity of Some Chiral Cyclic Esters Ⅱ
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作者 Ai Hua NIE Xiu Lin YE Qi Yi XING(Department of Chemistry,Pcking University,Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期141-144,共4页
A method for the analysis of the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray diffraction structures of some cyclic esters prepared by esteri... A method for the analysis of the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray diffraction structures of some cyclic esters prepared by esterification of L-(-)-2.3-O-methylidene threitol and L-(+)-2,3-O-isopropplidene threitol with alkanedioyl dichlorides and o-,m-,and p-phthaloyl dichlorides. 展开更多
关键词 Activity CL Studies on the Relationship between the Helical structure and optical Activity of Some Chiral Cyclic Esters
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Synthesis,Structure and Optical Properties of CdO Nanocrystals Directly Grown on Cd Foil
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作者 李勇 凌虹 +3 位作者 高磊 宋月丽 田明丽 周丰群 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期127-129,共3页
Semiconductor nanocrystals directly grown on the conducting metal can lower the contact resistance and can benefit the electron transfer between the semiconductor and the metal. In the present work, CdO nanocrystals a... Semiconductor nanocrystals directly grown on the conducting metal can lower the contact resistance and can benefit the electron transfer between the semiconductor and the metal. In the present work, CdO nanocrystals are directly synthesized on the conducting Cd foil through a simple solvothermal method. Cd foil is used as the Cd2+ source and the substrate. The average size of CdO nanocrystals is -23.1 nm by analyzing the XRD data. Moreover the growth mechanism is discussed. A hierarchic structure characterized by the nano rods and nano particles in the top and bottom layers, respectively, can be observed. From the UV-vis absorption analyzed by Taucs relation, the two different optical band gaps are obtained. The photoluminescence spectrum is obtained and studied. 展开更多
关键词 CDO Synthesis structure and optical Properties of CdO Nanocrystals Directly Grown on Cd Foil
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Synthesis,Crystal Structure and Optical Prosperities of a Carboxylic Acid Functionalized Carbazole Derivative
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作者 杨利 朱舒卷 +3 位作者 白向阳 张俊 许献云 孔林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期175-181,共7页
A novel carbazole derivative 2-cyano-3-(9-ethyl-9H-carbazol-3-yl)-acrylic acid ethyl ester(L) was designed and synthesized through Vilsmeier and Knoevenagelreactions, which was characterized by FT-IR, ~1H NMR and1... A novel carbazole derivative 2-cyano-3-(9-ethyl-9H-carbazol-3-yl)-acrylic acid ethyl ester(L) was designed and synthesized through Vilsmeier and Knoevenagelreactions, which was characterized by FT-IR, ~1H NMR and13 C NMR spectra. The crystal of L crystallizes in the monoclinic system, space group P21/c with a = 10.8298(15), b = 13.4660(19), c = 15.4358(16) ?, β = 131.214(6)o, V = 1693.4(4) ?~3, Z = 4, Dc = 1.249 g/cm^3, Mr = 318.36, μ = 0.082 mm-1, F(000) = 672, completeness to theta was 99.9% and GOOF = 1.091.Rint = 0.0338, R(I 〉2σ(I)) = 0.0631, w R(I 〉 2σ(I)) = 0.1861, R(all data) = 0.1027 andw R(all data) = 0.2105. There were three types of weak intermolecular interactions(C(8)–H(8)···N(2), C(14)–H(14)···O(2) and C(20B)– H(20B)···π)among the adjacent molecules to construct a three-dimensional single crystal. The UV-Vis spectra, fluorescence emission and time-dependent density functional theory(TD-DFT) calculation of L were studied and the results revealedthe existence of intramolecular charge transfer(ICT) process of L molecule. The optical properties indicated that it can be used as a potential candidate in the application oforganic light emitting diodes(OLEDs). 展开更多
关键词 carbazole ICT single-crystal structure optical properties
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Electronic structures and optical properties of HfO_2–TiO_2 alloys studied by first-principles GGA + U approach
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作者 李金平 孟松鹤 +2 位作者 杨程 陆汉涛 遠山貴巳 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期510-515,共6页
The phase diagram of HfO_2–TiO_2 system shows that when Ti content is less than 33.0 mol%, HfO_2–TiO_2 system is monoclinic; when Ti content increases from 33.0 mol% to 52.0 mol%, it is orthorhombic; when Ti content... The phase diagram of HfO_2–TiO_2 system shows that when Ti content is less than 33.0 mol%, HfO_2–TiO_2 system is monoclinic; when Ti content increases from 33.0 mol% to 52.0 mol%, it is orthorhombic; when Ti content reaches more than 52.0 mol%, it presents rutile phase. So, we choose the three phases of HfO_2–TiO_2 alloys with different Ti content values. The electronic structures and optical properties of monoclinic, orthorhombic and rutile phases of HfO_2–TiO_2 alloys are obtained by the first-principles generalized gradient approximation(GGA) +U approach, and the effects of Ti content and crystal structure on the electronic structures and optical properties of HfO_2–TiO_2 alloys are investigated. By introducing the Coulomb interactions of 5 d orbitals on Hf atom(U_1~d), those of 3 d orbitals on Ti atom(U_2~d), and those of 2 p orbitals on O atom(Up) simultaneously, we can improve the calculation values of the band gaps, where U_1~d, U_2~d, and Up values are 8.0 eV, 7.0 eV, and 6.0 eV for both the monoclinic phase and orthorhombic phase, and 8.0 eV, 7.0 eV, and 3.5 eV for the rutile phase. The electronic structures and optical properties of the HfO_2–TiO_2 alloys calculated by GGA +U_1~d(U_1~d= 8.0 eV) +U_2~d(U_2~d= 7.0 eV) +U^p(U^p= 6.0 eV or 3.5 eV) are compared with available experimental results. 展开更多
关键词 HfO2–TiO2 alloys GGA +U electronic structure optical properties
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Analysis and Modeling of k-regular and k-connected Protection Structure in Ultra-High Capacity Optical Networks
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作者 LI Xin HUANG Shanguo +3 位作者 ZHANG Jie ZHAO Yongli GU Wanyi WANG Yang 《China Communications》 SCIE CSCD 2015年第3期106-119,共14页
This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on ... This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on logical redundancy.The switching time of k&k protection structure is as quickly as ringbased protection in SDH network.It is the optimal protection structure in ultra-high capacity optical networks against multi-faults.We develop the linear programming model for k&k structure and propose a construction method for k&k structure design.Simulations are conducted for spare spectrum resources effi ciency of the pre-confi gured k&k structure under multi-faults on representative COST239 and NSFnet topologies.Numerical results show that the spare spectrum resources efficiency of k&k structure can reach the lower bound on logical redundancy in static networks.And it can largely improve spare spectrum resources effi ciency compared with p-cycles based protection structure without reducing protection effi ciency under dynamic traffi cs. 展开更多
关键词 multi-faults k-regular and k-connected structure ultra-high capacity optical networks
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Stress test and analysis based on SMS fiber structure with high sensitivity
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作者 张美芹 王冠军 +1 位作者 安永泉 王志斌 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期297-301,共5页
Single mode-multimode-single mode (SMS) sensor is widely used for parameters measurement, such as bending, dis-placement, temperature, strain, refractive index, etc. Generally, SMS sensor has advantages of simpl... Single mode-multimode-single mode (SMS) sensor is widely used for parameters measurement, such as bending, dis-placement, temperature, strain, refractive index, etc. Generally, SMS sensor has advantages of simple structure, low cost and easy layout, therefore it has become a research hotspot in recent years. In this paper, the multimode fiber with large core is used for manufacturing SMS structure with high sensitivity. Firstly, the multimode fiber with core/cladding diameters of 105/ 125 jitm has access to the system by means of single mode optical fiber. Secondly, SMS device structure is manufactured by welding the eccentric shaft of multimode optical fiber. Afterwards, mode interference effect and spectral response characteristics of the structure of single mode-multimode-single mode optical fiber are analyzed theoretically. Finally, with the help of a wide spectrum light source and a spectrum analyzer, the transmission spectra characteristics of SMS optical fiber with strain is tested. By observing the curve that the wave changes with stress, the sensitivity is calculated and it is consistent with theoretical value . 展开更多
关键词 SMS optical fiber structure optical spectrum analyzer (OSA) amplified spontaneous emission stress test
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First-Principles Study of Structural Stabilities, Electronic and Optical Properties of SrF2 under High Pressure 被引量:5
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作者 郝爱民 杨晓翠 +4 位作者 李杰 辛伟 张素红 张新宇 刘日平 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第7期259-262,共4页
An investigation of structural stabilities, electronic and optical properties of SrF2 under high pressure is conducted using a first-principles calculation based on density functional theory (DFT) with the plane wav... An investigation of structural stabilities, electronic and optical properties of SrF2 under high pressure is conducted using a first-principles calculation based on density functional theory (DFT) with the plane wave basis set as implemented in the CASTEP code. Our results predict that the second high-pressure phase of SrF2 is of a Ni2In- type structure, and demonstrate that the sequence of the pressure-induced phase transition of SrF2 is the fluorite structure (Fm3m) to the PbC12-type structure (Pnma), and to the Ni2In-type phase (P63/mmc). The first and second phase transition pressures are 5. 77 and 45.58 GPa, respectively. The energy gap increases initially with pressure in the Fm3m, and begins to decrease in the Pnma phases at 30 GPa. The band gap overlap metallization does not occur up to 210 GPa. The pressure effect on the optical properties is discussed. 展开更多
关键词 Condensed matter: electrical magnetic and optical Condensed matter: structural mechanical & thermal
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Structured Illumination Chip Based on Integrated Optics 被引量:1
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作者 刘勇 王辰 +3 位作者 Anastasia Nemkova 胡诗铭 李智勇 俞育德 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期46-49,共4页
A compact structured illumination chip based on integrated optics is proposed and fabricated on a silicon-on- insulator platform. Based on the simulation of Caussian beam interference, we adopt a chirped diffraction g... A compact structured illumination chip based on integrated optics is proposed and fabricated on a silicon-on- insulator platform. Based on the simulation of Caussian beam interference, we adopt a chirped diffraction grating to achieve a specific interference pattern. The experimental results match well with the simulations. The portability and flexibility of the structured illumination chip can be increased greatly through horizontal encapsulation. High levels of integration, compared with the conventional structured illumination approach, make this chip very compact, with a footprint of only around 1 mm2. The chip has no optical lenses and can be easily combined with a microfluidic system. These properties would make the chip very suitable for portable 3D scanner and compact super-resolution microscopy applications. 展开更多
关键词 of for structured Illumination Chip Based on Integrated Optics IS on SOI into been
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A transparent electromagnetic-shielding film based on one-dimensional metal–dielectric periodic structures 被引量:6
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作者 赵亚丽 马富花 +3 位作者 李旭峰 马江将 贾琨 魏学红 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期540-546,共7页
In this study, we designed and fabricated optical materials consisting of alternating ITO and Ag layers. This approach is considered to be a promising way to obtain a light-weight, ultrathin and transparent shielding ... In this study, we designed and fabricated optical materials consisting of alternating ITO and Ag layers. This approach is considered to be a promising way to obtain a light-weight, ultrathin and transparent shielding medium, which not only transmits visible light but also inhibits the transmission of microwaves, despite the fact that the total thickness of the Ag film is much larger than the skin depth in the visible range and less than that in the microwave region. Theoretical results suggest that a high dielectric/metal thickness ratio can enhance the broadband and improve the transmittance in the optical range. Accordingly, the central wavelength was found to be red-shifted with increasing dielectric/metal thickness ratio. A physical mechanism behind the controlling transmission of visible light is also proposed. Meanwhile, the electromagnetic shielding effectiveness of the prepared structures was found to exceed 40 dB in the range from 0.1 GHz to 18 GHz, even reaching up to 70 dB at 0.1 GHz, which is far higher than that of a single ITO film of the same thickness. 展开更多
关键词 transparent shields electromagnetic shielding effectiveness optical transmittance metal–dielectric periodic structure
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Design and Fabrication of an Er-Doped Silica Optical Fiber with Six Photosensitive Subcores 被引量:1
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作者 李坚 王静 +5 位作者 刘鹏 鲁韶华 毛向桥 江微微 宁提纲 简水生 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第7期147-149,共3页
A type of multi-core Er-doped photosensitive silica optical fiber (MC-EDPF) is proposed and fabricated, in which a high consistency Er-doped core is surrounded by six high consistency Ge-doped cores. The multi-core ... A type of multi-core Er-doped photosensitive silica optical fiber (MC-EDPF) is proposed and fabricated, in which a high consistency Er-doped core is surrounded by six high consistency Ge-doped cores. The multi-core design can overcome the difficulties encountered in the design and fabrication of single-core EDPFs through a modified chemical vapor deposition method combined with solution doping technology, and there is a conflict between high consistency Er doping and high consistency Ce doping. The absorption of MC-EDPFs achieved 15.876dB/m at 1550mm and lOdB/m at 98Ohm. The refleetivity of the fiber Bragg gratings (FBCs) written directly on the MC-EDPFs is as much as 96.84%. 展开更多
关键词 Optics quantum optics and lasers Condensed matter: structural mechanical & thermal
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