The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidenc...The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidence angles up to 60°.The CFSR consists of four functional layers separated by three dielectric slabs,which includes lossless metasurface-Ⅰ(MS-Ⅰ),loss metasurface-Ⅱ(MS-Ⅱ),loss metasurface-Ⅲ(MS-Ⅲ),and a three-dimensional metastructure(3D-MS).MS-Ⅰfunctions as a reflector for two absorption bands with a minimal insertion loss transmission window.MS-Ⅱis designed for high-frequency absorption.MS-Ⅲserves as a low-frequency absorption layer for CFSR and an impedance matching layer for MS-Ⅱ.The design methodologies for the transmission window in MS-III and the introduction of 3D-MS are key to achieving high-performance CFSR.The physical mechanisms of CFSR are explained through equivalent circuit model(ECM)analysis and impedance characterization.Finally,measurement results confirm that the proposed CFSR exhibits a−1 dB transmission band ranging from 8.79 to 10.41 GHz with a minimum insertion loss of 0.44 dB at 9.59 GHz;furthermore,the frequency range where reflection coefficient remains below−10 dB is measured to be between 3.33 and 18.00 GHz,aligning well with simulation outcomes.展开更多
In this paper, we first find finite travelling-wave solutions, and then investigate the short time development of interfaces for non-Newtonian diffusion equations with strong absorption. We show that the initial behav...In this paper, we first find finite travelling-wave solutions, and then investigate the short time development of interfaces for non-Newtonian diffusion equations with strong absorption. We show that the initial behavior of the interface depends on the concentration of the mass of u（x,0） near x=0. More precisely, we find a critical value of the concentration, which separates the heating front of interfaces from the cooling front of them.展开更多
Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consump- tion is a significant issue for information technology. Here we design an ＇electrically written and optically...Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consump- tion is a significant issue for information technology. Here we design an ＇electrically written and optically read＇ information storage device employing BiFeO3/A u heterostruetures with strong absorption resonance. The electro- optic effect is the basis for the device design, which arises from the strong absorption resonance in BiFeO3/Au heterostructures and the electrically tunable significant birefringence of the BiFeO3 film. We first construct a sim- ulation calculation of the BiFeO3/Au structure spectrum and identify absorption resonance and electro-optical modulation characteristics. Following a micro scale partition, the surface reflected light intensity of different polarization units is calculated. The results depend on electric polarization states of the BiFeO3 film, thus BiFeO3/Au heterostructures can essentially be designed as a type of electrically written and optically read infor- mation storage device by utilizing the scanning near-field optical microscopy technology based on the conductive silicon cantilever tip with nanofabricated aperture. This work will shed light on information storage technology.展开更多
The reduced strong absorption distance d_(S) and Coulomb barrier height V_(B) are extracted from the quarter-point recipe from a series of experimental elastic scattering angle distributions.The nuclei with different ...The reduced strong absorption distance d_(S) and Coulomb barrier height V_(B) are extracted from the quarter-point recipe from a series of experimental elastic scattering angle distributions.The nuclei with different binding energies are systematically studied as the projectile,including the tightly bound,weakly bound,and halo nuclei.It is found that the mean d_(S) for halo nuclei is significantly larger than that of tightly and weakly bound nuclei.The complex behavior of d_(S) regarding the binding energy and properties of the target is observed for halo nuclei.The linear relationship of the reduced distance with system size may be used to estimate the Coulomb barrier radius R_(B),which is difficult to obtain from fusion reactions.The rule of V_(B) concerning the Coulomb parameter z is in agreement with other theoretical barrier laws extracted from the fusion reaction.Furthermore,the reason why the binding energy or deformation has little effect on the linear relationship of V_(B) as a function of z is clarified.展开更多
Microwave absorbers(MAs)with broadband and strong microwave absorption capacities are urgently required to meet the demands of complex electromagnetic(EM)environments.Herein,a novel labyrinth multiresonant metastructu...Microwave absorbers(MAs)with broadband and strong microwave absorption capacities are urgently required to meet the demands of complex electromagnetic(EM)environments.Herein,a novel labyrinth multiresonant metastructure composed of a polyether-ether-ketone/flaky carbonyl iron(PEEK/CIP)magnetic composite was proposed and fabricated via 3D printing technology.A complex multiresonant cavity design was introduced,and the resonant loss area was significantly improved.Both broadband and high-efficiency microwave absorption performances were achieved.The multilayer labyrinth multiresonant metastructure was designed with gradient impedance.The effects of structural parameters on the absorbing properties were investigated and optimized.Experiments and simulations demonstrated the effectiveness of the design strategy.The designed metastructure with a 10 mm thickness exhibited a-10 dB absorption bandwidth at a frequency of 3.78–40 GHz and an absorption bandwidth below-15 dB at 7.5–36.5 GHz.Moreover,an excellent wide-angle absorption performance was observed for different polarization states,including transverse electric(TE)and transverse magnetic(TM)modes.The combination of a complex multiresonant metastructure design and 3D printing fabrication provides a facile route to considerably extend the absorption bandwidth and strength of electromagnetic absorbers.This work is expected to provide a promising strategy for further enhancing microwave absorption performance,and the designed metastructure possesses great application potential in stealth and electromagnetic compatibility technologies.展开更多
By transferring 100 nm gold-coated CVD monolayer graphene onto the well-polished surface of D-shaped fiber, we achieve a graphene in-line polarizer with a high polarization extinction ratio of ~27 d B and low insertio...By transferring 100 nm gold-coated CVD monolayer graphene onto the well-polished surface of D-shaped fiber, we achieve a graphene in-line polarizer with a high polarization extinction ratio of ~27 d B and low insertion loss of 5 d B at 1550 nm, meanwhile achieving a strong saturable absorption effect of 14%. The manufacture of this graphene in-line polarizer also simplifies the graphene transfer process. To explore the potential applications of the new device, we also demonstrate noise-like pulse generation and supercontinuum spectrum generation. By launching the designed graphene device into a fiber ring laser cavity, 51 nm bandwidth noise-like pulse is obtained. Then, launching the high-power noise-like pulse into high nonlinear fiber, a 1000 nm wide supercontinuum spectrum is obtained, which is favorable for sensing and nonlinearities scientific fields.展开更多
Photosensitization related to energy/electron transfer process is of great importance to natural photosynthesis.Herein,we proposed a promising strategy to improve the sensitizing ability of the typical photoactive MOF...Photosensitization related to energy/electron transfer process is of great importance to natural photosynthesis.Herein,we proposed a promising strategy to improve the sensitizing ability of the typical photoactive MOFs(UiO-Ir)by engineering its metal coordination center with NBI(1,8-naphthalenebenzimidizole)chromophore.The resulting MOFs(UiO-Ir-NBI)exhibited a strong sensitizing ability for significantly boosting photosynthesis.Impressively,the catalytic yield of 2-chloroethyl ethyl sulfoxide with UiO-Ir-NBI can reach 99%,over 6 times higher than that with UiO-Ir(16.4%).Moreover,UiO-Ir-NBI exhibited an excellent catalytic stability and a broad substrate tolerance,highlighting its great application prospect.Systematic investigations revealed that the strong visible light absorption,long excited state lifetime and efficient electron-hole separation of UiO-Ir-NBI greatly contributed to harvesting visible light and facilitating interface electron/energy transfer for efficient solar energy utilization.This work provides a new horizon to boost photosythesis of MOFs by engineering their metal sensitizing centers at a molecular level.展开更多
The authors prove that flat ground state solutions(i.e. minimizing the energy and with gradient vanishing on the boundary of the domain) of the Dirichlet problem associated to some semilinear autonomous elliptic equat...The authors prove that flat ground state solutions(i.e. minimizing the energy and with gradient vanishing on the boundary of the domain) of the Dirichlet problem associated to some semilinear autonomous elliptic equations with a strong absorption term given by a non-Lipschitz function are unstable for dimensions N = 1, 2 and they can be stable for N ≥ 3 for suitable values of the involved exponents.展开更多
Singlet fission(SF)has attracted much attention on account of its great potential for applications in high efficiency solar energy conversion.The major roadblock to realize this potential is rooted in the limited avai...Singlet fission(SF)has attracted much attention on account of its great potential for applications in high efficiency solar energy conversion.The major roadblock to realize this potential is rooted in the limited availability of practical SF material with strong absorption,suitable triplet energy level,an efficient SF process,and good chemical stability.Quinoidal structures feature an innate diradical character,which endows these skeletons with SF potential yet results in some structural instability.展开更多
Pn junctions based on single crystalline tellurium supersaturated silicon were formed by ion implantation followed by pulsed laser melting（PLM）.P type silicon wafers were implanted with 245 keV ^126Te^＋ to a dose o...Pn junctions based on single crystalline tellurium supersaturated silicon were formed by ion implantation followed by pulsed laser melting（PLM）.P type silicon wafers were implanted with 245 keV ^126Te^＋ to a dose of 2×10^15 ions/cm^2,after a PLM process（248 nm,laser fluence of 0.30 and 0.35 J/cm^2,1-5 pulses,duration 30 ns）,an n^＋ type single crystalline tellurium supersaturated silicon layer with high carrier density（highest concentration 4.10×10^19 cm^3,three orders of magnitude larger than the solid solution limit） was formed,it shows high broadband optical absorption from 400 to 2500 nm.Current-voltage measurements were performed on these diodes under dark and one standard sun（AM 1.5）,and good rectification characteristics were observed.For present results,the samples with 4-5 pulses PLM are best.展开更多
基金Project(2021RC3003) supported by the Hunan Science and Technology Innovation Talents Program,China。
文摘The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidence angles up to 60°.The CFSR consists of four functional layers separated by three dielectric slabs,which includes lossless metasurface-Ⅰ(MS-Ⅰ),loss metasurface-Ⅱ(MS-Ⅱ),loss metasurface-Ⅲ(MS-Ⅲ),and a three-dimensional metastructure(3D-MS).MS-Ⅰfunctions as a reflector for two absorption bands with a minimal insertion loss transmission window.MS-Ⅱis designed for high-frequency absorption.MS-Ⅲserves as a low-frequency absorption layer for CFSR and an impedance matching layer for MS-Ⅱ.The design methodologies for the transmission window in MS-III and the introduction of 3D-MS are key to achieving high-performance CFSR.The physical mechanisms of CFSR are explained through equivalent circuit model(ECM)analysis and impedance characterization.Finally,measurement results confirm that the proposed CFSR exhibits a−1 dB transmission band ranging from 8.79 to 10.41 GHz with a minimum insertion loss of 0.44 dB at 9.59 GHz;furthermore,the frequency range where reflection coefficient remains below−10 dB is measured to be between 3.33 and 18.00 GHz,aligning well with simulation outcomes.
基金Supported by the National Natural Science Foundation of China(Grant No.11071266)National Natural Science Foundation of China,Tian Yuan Special Foundation(Grant No.11226181)+1 种基金Scientific Research Fund of Sichuan Provincial Education Department(Grant No.13ZA0010)the Natural Science Foundation Project of China West Normal University(Grant No.12B024)
文摘In this paper, we first find finite travelling-wave solutions, and then investigate the short time development of interfaces for non-Newtonian diffusion equations with strong absorption. We show that the initial behavior of the interface depends on the concentration of the mass of u（x,0） near x=0. More precisely, we find a critical value of the concentration, which separates the heating front of interfaces from the cooling front of them.
基金Supported by the National Natural Science Foundation of China under Grant No 11304384the Research Project of National University of Defense Technology under Grant No JC13-07-02
文摘Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consump- tion is a significant issue for information technology. Here we design an ＇electrically written and optically read＇ information storage device employing BiFeO3/A u heterostruetures with strong absorption resonance. The electro- optic effect is the basis for the device design, which arises from the strong absorption resonance in BiFeO3/Au heterostructures and the electrically tunable significant birefringence of the BiFeO3 film. We first construct a sim- ulation calculation of the BiFeO3/Au structure spectrum and identify absorption resonance and electro-optical modulation characteristics. Following a micro scale partition, the surface reflected light intensity of different polarization units is calculated. The results depend on electric polarization states of the BiFeO3 film, thus BiFeO3/Au heterostructures can essentially be designed as a type of electrically written and optically read infor- mation storage device by utilizing the scanning near-field optical microscopy technology based on the conductive silicon cantilever tip with nanofabricated aperture. This work will shed light on information storage technology.
基金This study is supported by the National Key R&D Program of China(2022YFA1602302)the National Natural Science Foundation of China(12235020,12275360,12175314,12175313,U2167204)+3 种基金the Continuous Basic Scientific Research Project(WDJC-2019-13)the Leading Innovation Project(LC192209000701,LC202309000201)the project supported by the Director's Foundation of Department of Nuclear Physics,China Institute of Atomic Energy(12SZJJ-202305)the Young Talent Development Foundation(YC212212000101)。
文摘The reduced strong absorption distance d_(S) and Coulomb barrier height V_(B) are extracted from the quarter-point recipe from a series of experimental elastic scattering angle distributions.The nuclei with different binding energies are systematically studied as the projectile,including the tightly bound,weakly bound,and halo nuclei.It is found that the mean d_(S) for halo nuclei is significantly larger than that of tightly and weakly bound nuclei.The complex behavior of d_(S) regarding the binding energy and properties of the target is observed for halo nuclei.The linear relationship of the reduced distance with system size may be used to estimate the Coulomb barrier radius R_(B),which is difficult to obtain from fusion reactions.The rule of V_(B) concerning the Coulomb parameter z is in agreement with other theoretical barrier laws extracted from the fusion reaction.Furthermore,the reason why the binding energy or deformation has little effect on the linear relationship of V_(B) as a function of z is clarified.
基金supported by the Fundamental Research Funds for the Central Universities (Grant No.xzd012021041)the Analytical&Testing Center of Xi’an Jiaotong University for SEM analysis。
文摘Microwave absorbers(MAs)with broadband and strong microwave absorption capacities are urgently required to meet the demands of complex electromagnetic(EM)environments.Herein,a novel labyrinth multiresonant metastructure composed of a polyether-ether-ketone/flaky carbonyl iron(PEEK/CIP)magnetic composite was proposed and fabricated via 3D printing technology.A complex multiresonant cavity design was introduced,and the resonant loss area was significantly improved.Both broadband and high-efficiency microwave absorption performances were achieved.The multilayer labyrinth multiresonant metastructure was designed with gradient impedance.The effects of structural parameters on the absorbing properties were investigated and optimized.Experiments and simulations demonstrated the effectiveness of the design strategy.The designed metastructure with a 10 mm thickness exhibited a-10 dB absorption bandwidth at a frequency of 3.78–40 GHz and an absorption bandwidth below-15 dB at 7.5–36.5 GHz.Moreover,an excellent wide-angle absorption performance was observed for different polarization states,including transverse electric(TE)and transverse magnetic(TM)modes.The combination of a complex multiresonant metastructure design and 3D printing fabrication provides a facile route to considerably extend the absorption bandwidth and strength of electromagnetic absorbers.This work is expected to provide a promising strategy for further enhancing microwave absorption performance,and the designed metastructure possesses great application potential in stealth and electromagnetic compatibility technologies.
基金supported by National Natural Science Foundation of China(61322507,61090393 and 61575122)
文摘By transferring 100 nm gold-coated CVD monolayer graphene onto the well-polished surface of D-shaped fiber, we achieve a graphene in-line polarizer with a high polarization extinction ratio of ~27 d B and low insertion loss of 5 d B at 1550 nm, meanwhile achieving a strong saturable absorption effect of 14%. The manufacture of this graphene in-line polarizer also simplifies the graphene transfer process. To explore the potential applications of the new device, we also demonstrate noise-like pulse generation and supercontinuum spectrum generation. By launching the designed graphene device into a fiber ring laser cavity, 51 nm bandwidth noise-like pulse is obtained. Then, launching the high-power noise-like pulse into high nonlinear fiber, a 1000 nm wide supercontinuum spectrum is obtained, which is favorable for sensing and nonlinearities scientific fields.
基金supported by National Key R&D Program of China(No.2019YFA0705201)National Natural Science Foundation of China(No.22171209)。
文摘Photosensitization related to energy/electron transfer process is of great importance to natural photosynthesis.Herein,we proposed a promising strategy to improve the sensitizing ability of the typical photoactive MOFs(UiO-Ir)by engineering its metal coordination center with NBI(1,8-naphthalenebenzimidizole)chromophore.The resulting MOFs(UiO-Ir-NBI)exhibited a strong sensitizing ability for significantly boosting photosynthesis.Impressively,the catalytic yield of 2-chloroethyl ethyl sulfoxide with UiO-Ir-NBI can reach 99%,over 6 times higher than that with UiO-Ir(16.4%).Moreover,UiO-Ir-NBI exhibited an excellent catalytic stability and a broad substrate tolerance,highlighting its great application prospect.Systematic investigations revealed that the strong visible light absorption,long excited state lifetime and efficient electron-hole separation of UiO-Ir-NBI greatly contributed to harvesting visible light and facilitating interface electron/energy transfer for efficient solar energy utilization.This work provides a new horizon to boost photosythesis of MOFs by engineering their metal sensitizing centers at a molecular level.
基金supported by the projects of the DGISPI(Spain)(Ref.MTM2011-26119,MTM2014-57113)the UCM Research Group MOMAT(Ref.910480)
文摘The authors prove that flat ground state solutions(i.e. minimizing the energy and with gradient vanishing on the boundary of the domain) of the Dirichlet problem associated to some semilinear autonomous elliptic equations with a strong absorption term given by a non-Lipschitz function are unstable for dimensions N = 1, 2 and they can be stable for N ≥ 3 for suitable values of the involved exponents.
基金supported by the National Natural Science Foundation of China(nos.22005210,21833005,and 21833006).
文摘Singlet fission(SF)has attracted much attention on account of its great potential for applications in high efficiency solar energy conversion.The major roadblock to realize this potential is rooted in the limited availability of practical SF material with strong absorption,suitable triplet energy level,an efficient SF process,and good chemical stability.Quinoidal structures feature an innate diradical character,which endows these skeletons with SF potential yet results in some structural instability.
基金supported by the Beijing Natural Science Foundation(No.4122080)the State Key Development Program for Basic Research of China(No.2012CB934202)the CAS Program(No.Y072051002)
文摘Pn junctions based on single crystalline tellurium supersaturated silicon were formed by ion implantation followed by pulsed laser melting（PLM）.P type silicon wafers were implanted with 245 keV ^126Te^＋ to a dose of 2×10^15 ions/cm^2,after a PLM process（248 nm,laser fluence of 0.30 and 0.35 J/cm^2,1-5 pulses,duration 30 ns）,an n^＋ type single crystalline tellurium supersaturated silicon layer with high carrier density（highest concentration 4.10×10^19 cm^3,three orders of magnitude larger than the solid solution limit） was formed,it shows high broadband optical absorption from 400 to 2500 nm.Current-voltage measurements were performed on these diodes under dark and one standard sun（AM 1.5）,and good rectification characteristics were observed.For present results,the samples with 4-5 pulses PLM are best.
