Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors...Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors has been previously reported in ambient-pressure tetragonal phase.However,to comprehensively ascertain the nature of superconductivity,the investigation of BiS_(2)-based system in high-pressure structure is highly desirable.In this work,we carried out the first-principles calculations of phonon spectra and superconductivity in high-pressure monoclinic phase of LaO_(0.5)F_(0.5)BiS_(2)with ^(32)S and ^(34)S,and observed that the corresponding isotope coefficient is 0.13≤α≤0.20.This value is much greater than that of BiS_(2)-based superconductors in ambient-pressure phase,but slightly smaller than that of conventional MgB_2.Taking into account the calculated T_(c) lower than experimental results,we finally conclude that the moderate phonon-mediated pairing plays a significant role in forming superconductivity of BiS_(2)-based system in high-pressure phase,moreover,the cooperative multiple paring interactions should also be considered.展开更多
We present a design and development of a high-performance light-emitting diode(LED)-side-pumped Nd:YAG rod laser with strong pulse energy,high efficiency,and consistency,very good beam quality,and high uniform pumping...We present a design and development of a high-performance light-emitting diode(LED)-side-pumped Nd:YAG rod laser with strong pulse energy,high efficiency,and consistency,very good beam quality,and high uniform pumping intensity in the active area which reduces the effects of thermal gradient significantly.A five-dimensional 810 nm LED array with a full width of 30 nm at half maximum was intended to achieve high coupling efficiency by putting the LED array as close as possible to the side of the Nd:YAG laser rod for overcoming the large pumped divergence.Under 2.25 J pump energy,maximum single pulse energy of 35.86 mJ with duration of 1.24μs at 1063.68 nm was obtained,equivalent to optical efficiency of 1.59%and a slope efficiency of 2.53%.The laser was set to repeat at a rate of 10 Hz with a beam quality factor of𝑀M^(2)_(x)=2.94 and𝑀M^(2)_(y)=3.35,as well as with the output power stability of<4.1%(root mean square)and<7.3%(peak to peak).To the best of our ability,this is the highest performance for an LED-side-pumped Nd:YAG rod laser oscillator with a 10-mJ-level output ever reported.展开更多
Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the p...Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the past few decades,the research on flexible electronic devices based on organic materials has witnessed rapid development and substantial achievements,and inorganic semiconductors are also now beginning to shine in the field of flexible electronics.As validated by the latest research,some of the inorganic semiconductors,particularly those at low dimension,unexpectedly exhibited excellent mechanical flexibility on top of superior electrical properties.Herein,we bring together a comprehensive analysis on the recently burgeoning low-dimension inorganic semiconductor materials in flexible electronics,including one-dimensional(1D)inorganic semiconductor nanowires(NWs)and two-dimensional(2D)transition metal dichalcogenides(TMDs).The fundamental electrical properties,optical properties,mechanical properties and strain engineering of materials,and their performance in flexible device applications are discussed in detail.We also propose current challenges and predict future development directions including material synthesis and device fabrication and integration.展开更多
The photonic spin Hall effect(PSHE),characterized by two splitting beams with opposite spins,has great potential applications in nano-photonic devices,optical sensing fields,and precision metrology.We present the sign...The photonic spin Hall effect(PSHE),characterized by two splitting beams with opposite spins,has great potential applications in nano-photonic devices,optical sensing fields,and precision metrology.We present the significant enhancement of terahertz(THz)PSHE by taking advantage of the optical Tamm state(OTS)in In Sb-distributed Bragg reflector(DBR)structure.The spin shift of reflected light can be dynamically tuned by the structural parameters(e.g.the thickness)of the InSb-DBR structure as well as the temperature,and the maximum spin shift for a horizontally polarized incident beam at 1.1 THz can reach up to 11.15 mm.Moreover,we propose a THz gas sensing device based on the enhanced PSHE via the strong excitation of OTS for the InSb-DBR structure with a superior intensity sensitivity of 5.873×10^(4)mm/RIU and good stability.This sensor exhibits two orders of magnitude improvement compared with the similar PSHE sensor based on In Sb-supported THz long-range surface plasmon resonance.These findings may provide an alternative way for the enhanced PSHE and offer the opportunity for developing new optical sensing devices.展开更多
Using an improved particle swarm optimization algorithm(IPSO)to drive a transfer matrix method,a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity is realized in plasma-embedded p...Using an improved particle swarm optimization algorithm(IPSO)to drive a transfer matrix method,a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity is realized in plasma-embedded photonic crystals arranged in a structure composed of periodic and quasi-periodic sequences on a normalized scale.The effective dielectric function,which determines the absorption of the plasma,is subject to the basic parameters of the plasma,causing the absorption of the proposed absorber to be easily modulated by these parameters.Compared with other quasi-periodic sequences,the Octonacci sequence is superior both in relative bandwidth and absolute bandwidth.Under further optimization using IPSO with 14 parameters set to be optimized,the absorption characteristics of the proposed structure with different numbers of layers of the smallest structure unit N are shown and discussed.IPSO is also used to address angular insensitive nonreciprocal ultrawide bandwidth absorption,and the optimized result shows excellent unidirectional absorbability and angular insensitivity of the proposed structure.The impacts of the sequence number of quasi-periodic sequence M and collision frequency of plasma1ν1 to absorption in the angle domain and frequency domain are investigated.Additionally,the impedance match theory and the interference field theory are introduced to express the findings of the algorithm.展开更多
A monolithic integrated two-section distributed feedback(TS-DFB)semiconductor laser for high-speed direct modulation is proposed and analyzed theoretically.The grating structure of the TS-DFB laser is designed by the ...A monolithic integrated two-section distributed feedback(TS-DFB)semiconductor laser for high-speed direct modulation is proposed and analyzed theoretically.The grating structure of the TS-DFB laser is designed by the reconstructionequivalent-chirp(REC)technique,which can reduce the manufacturing cost and difficulty,and achieve high wavelength controlling accuracy.The detuned loading effect and the photon-photon resonance(PPR)effect are utilized to enhance the modulation bandwidth of the TS-DFB laser,exceeding 37 GHz,while that of the conventional one-section DFB laser is only 16 GHz.When the bit rate of the non-return-to-zero(NRZ)signal reaches 55 Gb/s,a clear eye diagram with large opening can still be obtained.These results show that the proposed method can enhance the modulation bandwidth of DFB laser significantly.展开更多
We theoretically investigate the propagation characteristics of spin waves in skyrmion-based magnonic crystals. It is found that the dispersion relation can be manipulated by strains through magneto-elastic coupling. ...We theoretically investigate the propagation characteristics of spin waves in skyrmion-based magnonic crystals. It is found that the dispersion relation can be manipulated by strains through magneto-elastic coupling. Especially, the allowed bands and forbidden bands in dispersion relations shift to higher frequency with strain changing from compressive to tensile,while shifting to lower frequency with strain changing from tensile to compressive. We also confirm that the spin wave with specific frequency can pass the magnonic crystal or be blocked by tuning the strains. The result provides an advanced platform for studying the tunable skyrmion-based spin wave devices.展开更多
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year...Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.展开更多
We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave ...We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave operation conditions,a maximum output power of 1319.08 nm wavelength was achieved at 11.26 W at a repetition rate of 100 Hz.展开更多
Vertically stacking two-dimensional(2D)materials with small azimuthal deviation or lattice mismatch generate distinctive global structural periodicity and symmetry,revealed as the moirésuperlattices(MSLs).Manipul...Vertically stacking two-dimensional(2D)materials with small azimuthal deviation or lattice mismatch generate distinctive global structural periodicity and symmetry,revealed as the moirésuperlattices(MSLs).Manipulating the interlayer twist angle enables the modification of the electronic structure of 2D materials to explore the advanced applications.Although extraordinary progress has been achieved in the unique structure and emergent properties of MSLs,the investigation of the catalytic applications of MSLs materials is still in its infancy.It is therefore very urgent to summarize the advanced development of MSLs in the field of catalysis.In this review,we firstly summarize the advanced fabrication and high-resolution characterization techniques of the MSLs materials,as well as their novel properties related to catalysis represented by electrocatalytic hydrogen evolution reaction(HER).Then,all the MSLs materials such as MoS_(2),WS_(2),and Ru serving as electrocatalysts for HER are further reviewed in detail.Finally,we outline the current challenges as well as the experimental and theoretical strategies to advance the development of function-oriented MSLs materials for catalysis.This review aims to provide profound insight into the wide applications of this novel material platform in catalytic field.展开更多
The unique structural features represented by micro-nanoneedle tip structure reflect wonderful physical and chemical properties.The tip effect includes the concentration of energy such as electrons,photons and magneti...The unique structural features represented by micro-nanoneedle tip structure reflect wonderful physical and chemical properties.The tip effect includes the concentration of energy such as electrons,photons and magnetism in the tip region,which has promising applications in the fields of energy conversion,water capture,environmental restoration and so on.In this review,a comprehensive and systematic summary of the latest advances in the application of the tip effect in different fields is provided.Utilizing advanced Finite Difference Time Domain simulation,we further propose our understanding of the fundamental mechanism of the tip effect induced by micro-nanostructure.However,we need to forge the present study to further reveal the essential law of the tip effect from the perspective of theoretical calculations.This review would provide a solid foundation for further development and application of the tip effect.展开更多
The rapid evolution of portable and wearable electronic devices has fueled the development of smart functional textiles that are able to conduct electricity,sense body movements,or store energy.One main challenge inhi...The rapid evolution of portable and wearable electronic devices has fueled the development of smart functional textiles that are able to conduct electricity,sense body movements,or store energy.One main challenge inhibiting the further development of functional textile-based electronics is the lack of robust functional fibers with suitable electrical,electrochemical and sensing functionalities.MXenes,an emerging family of two-dimensional(2D)materials,have shown to be promising candidates for producing functional fibers due to their exceptional electrical and electrochemical properties combined with solution processability.The unique ability of MXenes to readily form liquid crystal phases in various solvents has allowed them to generate additive-free fibers using a wet spinning process.In this work,we review the recent exciting developments in the fabrication of neat MXenes fibers and present a critical evaluation of practical challenges in MXenes processing that influence the macroscale material properties and the performance of the subsequent devices.We also provide our assessment for the future opportunities and challenges in producing MXene fibers to help pave the way for their widespread use in advanced wearable applications.展开更多
Controlling architecture of hierarchical microstructures in liquid crystals(LCs]plays a crucial role in the development of novel soft-matter-based devices.Chiral LC fingerprints are considered as a prospective candida...Controlling architecture of hierarchical microstructures in liquid crystals(LCs]plays a crucial role in the development of novel soft-matter-based devices.Chiral LC fingerprints are considered as a prospective candidate for various applications;however,the efficient and real-time command of fingerprint landscapes still needs to be improved.Here,we achieve elaborate rotational fingerprint superstructures via dual photopatterning semifree chiral LC films,which combine the photoalignment technique and a dynamic light patterning process.An intriguing spatial-temporal rotational behavior is presented during the patterning of chiral superstructures.This work opens new avenues for the applications of chiral LCs in soft actuators,sensing,and micromanufacturing.展开更多
We propose magnetized gyromagnetic photonic crystals(MGPCs)composed of indium antimonide(InSb)and yttrium iron garnet ferrite(YIGF)layers,which possess the properties of nonreciprocal wide-angle bidirectional absorpti...We propose magnetized gyromagnetic photonic crystals(MGPCs)composed of indium antimonide(InSb)and yttrium iron garnet ferrite(YIGF)layers,which possess the properties of nonreciprocal wide-angle bidirectional absorption.Periodical defects in the MGPCs work as filters.Absorption bands(ABs)for the positive and negative propagations arise from the optical Tamm state and resonance in cavities respectively,and they prove to share no overlaps in the studied frequency range.Givenω=2.0138 THz,for the positive propagation,the ABs in the high-frequency range are localized in the interval between 0.66ωand 0.88ω.In the angular range,the ABs for the TE and TM waves reach 60°and 51°,separately.For the negative propagation,the ABs in the low-frequency range are localized in the interval between 0.13ωand 0.3ω.The AB s extend to 60°for the TE waves and 80.4°for the TM waves.There also exists a narrow frequency band in a lower frequency range.The relevant factors,which include the external temperature,the magnetic fields applied to the YIGF,the refractive index of the impedance matching layer,and the defect thickness,are adjusted to investigate the effects on the ABs.All the numerical simulations are based on the transfer matrix method.This work provides an approach to designs of isolators and so on.展开更多
Electrochemical gas evolution reactions are common but essential in many electrochemical processes including water electrolysis.During these processes,gas bubbles are constantly nucleating on reaction interfaces in el...Electrochemical gas evolution reactions are common but essential in many electrochemical processes including water electrolysis.During these processes,gas bubbles are constantly nucleating on reaction interfaces in electrolyte and consequently exert an impact on catalysts and the performance.In the past few decades,extensive studies have been conducted to characterize bubbles with emerging advanced technologies,manage behaviors of bubbles,and apply bubbles to various domains.In this review,we summarize representative discoveries as well as recent advancements in electrochemical gas evolution reactions from the perspective of gas bubbles.Finally,we end up this review with a profound outlook on future research topics from the combination of experiments and theoretical techniques,non-negligible bubble effects,gravity-free situation,and reactions under practical industrial conditions.展开更多
Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel...Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel capacity. Existing hyperentanglement sources mainly focus on the generation of the hyperentanglement in two DOFs. In this paper, we design the generation protocols for three kinds of hyperentanglement encoded in three DOFs with the practical coherent pulses sources, including the polarization-frequency-space hyperentanglement, the polarization-frequency-time-bin hyperentanglement, and the polarizationspace-time-bin hyperentanglement. These protocols exploit the spontaneous parametric down-conversion(SPDC) process and the Sagnac interferometer. The three protocols are all based on feasible experimental condition and may have potential applications in future hyperentanglement-based quantum communication and quantum information processing protocols.展开更多
The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power dens...The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power density,and good safety,are considered ideal candidates.Nevertheless,the relatively low energy density restricts their practical applications.With a large dielectric constant of 18-46,Ta_(2)O_(5)-based materials typically exhibit excellent electron-binding ability,which is critical for enhancing the energy density of supercapacitors.In this work,the free-standingβ-Ta_(2)O_(5)/single-walled carbon nanotubes(SWCNTs)composite film was prepared,with a highβ-Ta_(2)O_(5)loading of over 70%.By anchoringβ-Ta_(2)O_(5)nanoparticles onto the surface of SWCNTs,the system’s flexibility and conductivity were significantly enhanced,which also facilitated the intercalation electrodynamics of metal cations.As a result,the flexibleβ-Ta_(2)O_(5)/SWCNTs film exhibits excellent Li-ion storage performance,with a high volumetric specific capacitance of 392.3 F cm^(-3)at the scan rate of 10 mV s^(-1)and 198.9 F cm^(-3)at 500 mV s^(-1).In addition,the asymmetric device,assembled by theβ-Ta_(2)O_(5)/SWCNTs and activated carbon films,shows a high energy density of 45.5 Wh kg^(-1)at the power density of 10.8 kW kg^(-1).This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.展开更多
Self-assembled architectures of soft matter have fascinated scientists for centuries due to their unique physical properties originated from controllable orientational and/or positional orders,and diverse optic and ph...Self-assembled architectures of soft matter have fascinated scientists for centuries due to their unique physical properties originated from controllable orientational and/or positional orders,and diverse optic and photonic applications.If one could know how to design,fabricate,and manipulate these optical microstructures in soft matter systems,such as liquid crystals(LCs),that would open new opportunities in both scientific research and practical applications,such as the interaction between light and soft matter,the intrinsic assembly of the topological patterns,and the multidimensional control of the light(polarization,phase,spatial distribution,propagation direction).Here,we summarize recent progresses in self-assembled optical architectures in typical thermotropic LCs and bio-based lyotropic LCs.After briefly introducing the basic definitions and properties of the materials,we present the manipulation schemes of various LC microstructures,especially the topological and topographic configurations.This work further illustrates external-stimuli-enabled dynamic controllability of self-assembled optical structures of these soft materials,and demonstrates several emerging applications.Lastly,we discuss the challenges and opportunities of these materials towards soft matter photonics,and envision future perspectives in this field.展开更多
Heteroatom doping is a promising approach to enhance catalytic activity by modulating physical properties,electronic structure,and reaction pathway.Herein,we demonstrate that appropriate Ni-doping could trigger a pref...Heteroatom doping is a promising approach to enhance catalytic activity by modulating physical properties,electronic structure,and reaction pathway.Herein,we demonstrate that appropriate Ni-doping could trigger a preferential transition of the basal plane from 2H(trigonal prismatic)to 1T′(clustered Mo)by inducing lattice distortion and S vacancy(SV)and thus dramatically facilitate its catalytic hydrogen evolution activity.It is noteworthy that the unique catalysts did possess superior catalytic performance of hydrogen evolution reaction(HER).The rate of photocatalytic hydrogen evolution could reach 20.45 mmol·g^(−1)·h^(−1) and reduced only slightly in the long period of the photocatalytic process.First-principles calculations reveal that the distorted Ni-1T′-MoS_(2) with SV could generate favorable water adsorption energy(Ead(H_(2)O))and Gibbs free energy of hydrogen adsorption(∆GH).This work exhibits a facile and promising pathway for synergistically regulating physical properties,electronic structure,or wettability based on the doping strategy for designing HER electrocatalysts.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12175107)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY219087 and NY220038)。
文摘Isotope effect on superconductive transition temperature(T_c)is an essential indicator to examine whether the mechanism of superconductors is conventional.Unconventional isotope effect of BiS_(2)-based superconductors has been previously reported in ambient-pressure tetragonal phase.However,to comprehensively ascertain the nature of superconductivity,the investigation of BiS_(2)-based system in high-pressure structure is highly desirable.In this work,we carried out the first-principles calculations of phonon spectra and superconductivity in high-pressure monoclinic phase of LaO_(0.5)F_(0.5)BiS_(2)with ^(32)S and ^(34)S,and observed that the corresponding isotope coefficient is 0.13≤α≤0.20.This value is much greater than that of BiS_(2)-based superconductors in ambient-pressure phase,but slightly smaller than that of conventional MgB_2.Taking into account the calculated T_(c) lower than experimental results,we finally conclude that the moderate phonon-mediated pairing plays a significant role in forming superconductivity of BiS_(2)-based system in high-pressure phase,moreover,the cooperative multiple paring interactions should also be considered.
基金supported by Nanjing University of Posts and Telecommunications Foundation(Grant Nos.JUH219002 and JUH219007)Key Laboratory of Functional Crystals and Laser Technology,TIPC,CAS Foundation(Grant No.FCLT 202201).
文摘We present a design and development of a high-performance light-emitting diode(LED)-side-pumped Nd:YAG rod laser with strong pulse energy,high efficiency,and consistency,very good beam quality,and high uniform pumping intensity in the active area which reduces the effects of thermal gradient significantly.A five-dimensional 810 nm LED array with a full width of 30 nm at half maximum was intended to achieve high coupling efficiency by putting the LED array as close as possible to the side of the Nd:YAG laser rod for overcoming the large pumped divergence.Under 2.25 J pump energy,maximum single pulse energy of 35.86 mJ with duration of 1.24μs at 1063.68 nm was obtained,equivalent to optical efficiency of 1.59%and a slope efficiency of 2.53%.The laser was set to repeat at a rate of 10 Hz with a beam quality factor of𝑀M^(2)_(x)=2.94 and𝑀M^(2)_(y)=3.35,as well as with the output power stability of<4.1%(root mean square)and<7.3%(peak to peak).To the best of our ability,this is the highest performance for an LED-side-pumped Nd:YAG rod laser oscillator with a 10-mJ-level output ever reported.
基金supported by the Natural Science Foundation of China(No.51902101)Natural Science Foundation of Jiangsu Province(No.BK20201381)+1 种基金Science Foundation of Nanjing University of Posts and Telecommunications(No.NY219144)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX22_0254).
文摘Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the past few decades,the research on flexible electronic devices based on organic materials has witnessed rapid development and substantial achievements,and inorganic semiconductors are also now beginning to shine in the field of flexible electronics.As validated by the latest research,some of the inorganic semiconductors,particularly those at low dimension,unexpectedly exhibited excellent mechanical flexibility on top of superior electrical properties.Herein,we bring together a comprehensive analysis on the recently burgeoning low-dimension inorganic semiconductor materials in flexible electronics,including one-dimensional(1D)inorganic semiconductor nanowires(NWs)and two-dimensional(2D)transition metal dichalcogenides(TMDs).The fundamental electrical properties,optical properties,mechanical properties and strain engineering of materials,and their performance in flexible device applications are discussed in detail.We also propose current challenges and predict future development directions including material synthesis and device fabrication and integration.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12175107 and 12004194)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant No.NY220030)
文摘The photonic spin Hall effect(PSHE),characterized by two splitting beams with opposite spins,has great potential applications in nano-photonic devices,optical sensing fields,and precision metrology.We present the significant enhancement of terahertz(THz)PSHE by taking advantage of the optical Tamm state(OTS)in In Sb-distributed Bragg reflector(DBR)structure.The spin shift of reflected light can be dynamically tuned by the structural parameters(e.g.the thickness)of the InSb-DBR structure as well as the temperature,and the maximum spin shift for a horizontally polarized incident beam at 1.1 THz can reach up to 11.15 mm.Moreover,we propose a THz gas sensing device based on the enhanced PSHE via the strong excitation of OTS for the InSb-DBR structure with a superior intensity sensitivity of 5.873×10^(4)mm/RIU and good stability.This sensor exhibits two orders of magnitude improvement compared with the similar PSHE sensor based on In Sb-supported THz long-range surface plasmon resonance.These findings may provide an alternative way for the enhanced PSHE and offer the opportunity for developing new optical sensing devices.
文摘Using an improved particle swarm optimization algorithm(IPSO)to drive a transfer matrix method,a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity is realized in plasma-embedded photonic crystals arranged in a structure composed of periodic and quasi-periodic sequences on a normalized scale.The effective dielectric function,which determines the absorption of the plasma,is subject to the basic parameters of the plasma,causing the absorption of the proposed absorber to be easily modulated by these parameters.Compared with other quasi-periodic sequences,the Octonacci sequence is superior both in relative bandwidth and absolute bandwidth.Under further optimization using IPSO with 14 parameters set to be optimized,the absorption characteristics of the proposed structure with different numbers of layers of the smallest structure unit N are shown and discussed.IPSO is also used to address angular insensitive nonreciprocal ultrawide bandwidth absorption,and the optimized result shows excellent unidirectional absorbability and angular insensitivity of the proposed structure.The impacts of the sequence number of quasi-periodic sequence M and collision frequency of plasma1ν1 to absorption in the angle domain and frequency domain are investigated.Additionally,the impedance match theory and the interference field theory are introduced to express the findings of the algorithm.
基金the National Key Research and Development Program of China(Grant No.2020YFB2205804)the National Natural Science Foundation of China(Grant Nos.61974165 and Grant 61975075)the National Natural Science Foundation of China for the Youth,China(Grant No.62004105)。
文摘A monolithic integrated two-section distributed feedback(TS-DFB)semiconductor laser for high-speed direct modulation is proposed and analyzed theoretically.The grating structure of the TS-DFB laser is designed by the reconstructionequivalent-chirp(REC)technique,which can reduce the manufacturing cost and difficulty,and achieve high wavelength controlling accuracy.The detuned loading effect and the photon-photon resonance(PPR)effect are utilized to enhance the modulation bandwidth of the TS-DFB laser,exceeding 37 GHz,while that of the conventional one-section DFB laser is only 16 GHz.When the bit rate of the non-return-to-zero(NRZ)signal reaches 55 Gb/s,a clear eye diagram with large opening can still be obtained.These results show that the proposed method can enhance the modulation bandwidth of DFB laser significantly.
文摘We theoretically investigate the propagation characteristics of spin waves in skyrmion-based magnonic crystals. It is found that the dispersion relation can be manipulated by strains through magneto-elastic coupling. Especially, the allowed bands and forbidden bands in dispersion relations shift to higher frequency with strain changing from compressive to tensile,while shifting to lower frequency with strain changing from tensile to compressive. We also confirm that the spin wave with specific frequency can pass the magnonic crystal or be blocked by tuning the strains. The result provides an advanced platform for studying the tunable skyrmion-based spin wave devices.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51902101 and 21875203)the Natural Science Foundation of Hunan Province(Nos.2021JJ40044 and 2023JJ50287)Natural Science Foundation of Jiangsu Province(No.BK20201381).
文摘Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.
基金Nanjing University of Posts and Telecommunications Foundation(Grant Nos.JUH219002 and JUH219007)Key Laboratory of Functional Crystals and Laser Technology,TIPC,CAS Foundation(Grant No.FCLT 202201)。
文摘We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave operation conditions,a maximum output power of 1319.08 nm wavelength was achieved at 11.26 W at a repetition rate of 100 Hz.
基金This work was financially supported by the National Funds for Distinguished Young Scientists(No.61825503)the National Natural Science Foundation of China(Nos.51902101,61775101,and 61804082)+2 种基金the Youth Natural Science Foundation of Hunan Province(No.2021JJ40044)Natural Science Foundation of Jiangsu Province(No.BK20201381)Science Foundation of Nanjing University of Posts and Telecommunications(No.NY219144).
文摘Vertically stacking two-dimensional(2D)materials with small azimuthal deviation or lattice mismatch generate distinctive global structural periodicity and symmetry,revealed as the moirésuperlattices(MSLs).Manipulating the interlayer twist angle enables the modification of the electronic structure of 2D materials to explore the advanced applications.Although extraordinary progress has been achieved in the unique structure and emergent properties of MSLs,the investigation of the catalytic applications of MSLs materials is still in its infancy.It is therefore very urgent to summarize the advanced development of MSLs in the field of catalysis.In this review,we firstly summarize the advanced fabrication and high-resolution characterization techniques of the MSLs materials,as well as their novel properties related to catalysis represented by electrocatalytic hydrogen evolution reaction(HER).Then,all the MSLs materials such as MoS_(2),WS_(2),and Ru serving as electrocatalysts for HER are further reviewed in detail.Finally,we outline the current challenges as well as the experimental and theoretical strategies to advance the development of function-oriented MSLs materials for catalysis.This review aims to provide profound insight into the wide applications of this novel material platform in catalytic field.
基金This work was financially supported by the Natural Science Foundation of China(No.51902101)Natural Science Foundation of Jiangsu Province(No.BK20201381)+1 种基金Science Foundation of Nanjing University of Posts and Telecommunications(No.NY219144)the National College Student Innovation and Entrepreneurship Training Program(No.202210293017Z).
文摘The unique structural features represented by micro-nanoneedle tip structure reflect wonderful physical and chemical properties.The tip effect includes the concentration of energy such as electrons,photons and magnetism in the tip region,which has promising applications in the fields of energy conversion,water capture,environmental restoration and so on.In this review,a comprehensive and systematic summary of the latest advances in the application of the tip effect in different fields is provided.Utilizing advanced Finite Difference Time Domain simulation,we further propose our understanding of the fundamental mechanism of the tip effect induced by micro-nanostructure.However,we need to forge the present study to further reveal the essential law of the tip effect from the perspective of theoretical calculations.This review would provide a solid foundation for further development and application of the tip effect.
基金The authors acknowledge financial support from the National Natural Science Foundation of China(No.22105106)the Natural Science Foundation of Jiangsu Province of China(No.BK20210603)+1 种基金Nanjing Science and Technology Innovation Project for overseas Students,Start-up Funding from NUPTSF(No.NY221003)Research Grant from the Royal Society,UK(No.RGS\R1\221044).
文摘The rapid evolution of portable and wearable electronic devices has fueled the development of smart functional textiles that are able to conduct electricity,sense body movements,or store energy.One main challenge inhibiting the further development of functional textile-based electronics is the lack of robust functional fibers with suitable electrical,electrochemical and sensing functionalities.MXenes,an emerging family of two-dimensional(2D)materials,have shown to be promising candidates for producing functional fibers due to their exceptional electrical and electrochemical properties combined with solution processability.The unique ability of MXenes to readily form liquid crystal phases in various solvents has allowed them to generate additive-free fibers using a wet spinning process.In this work,we review the recent exciting developments in the fabrication of neat MXenes fibers and present a critical evaluation of practical challenges in MXenes processing that influence the macroscale material properties and the performance of the subsequent devices.We also provide our assessment for the future opportunities and challenges in producing MXene fibers to help pave the way for their widespread use in advanced wearable applications.
基金supported by the National Key Research and Development Program of China(Nos.2021YFA1202000 and 2022YFA1405000)the National Natural Science Foundation of China(No.52003115)+2 种基金the Natural Science Foundation of Jiangsu Province,Major Project(No.BK20212004)the Natural Science Foundation of Jiangsu Province(No.BK20200320)the support of Xiaomi Young Scholar program。
文摘Controlling architecture of hierarchical microstructures in liquid crystals(LCs]plays a crucial role in the development of novel soft-matter-based devices.Chiral LC fingerprints are considered as a prospective candidate for various applications;however,the efficient and real-time command of fingerprint landscapes still needs to be improved.Here,we achieve elaborate rotational fingerprint superstructures via dual photopatterning semifree chiral LC films,which combine the photoalignment technique and a dynamic light patterning process.An intriguing spatial-temporal rotational behavior is presented during the patterning of chiral superstructures.This work opens new avenues for the applications of chiral LCs in soft actuators,sensing,and micromanufacturing.
基金Project supported by the College Student Innovation Training Program of Nanjing University of Posts and Telecommunicationsthe Jiangsu Agriculture Science and Technology Innovation Fund(JASTIF)(Grant No.CX(21)3187)。
文摘We propose magnetized gyromagnetic photonic crystals(MGPCs)composed of indium antimonide(InSb)and yttrium iron garnet ferrite(YIGF)layers,which possess the properties of nonreciprocal wide-angle bidirectional absorption.Periodical defects in the MGPCs work as filters.Absorption bands(ABs)for the positive and negative propagations arise from the optical Tamm state and resonance in cavities respectively,and they prove to share no overlaps in the studied frequency range.Givenω=2.0138 THz,for the positive propagation,the ABs in the high-frequency range are localized in the interval between 0.66ωand 0.88ω.In the angular range,the ABs for the TE and TM waves reach 60°and 51°,separately.For the negative propagation,the ABs in the low-frequency range are localized in the interval between 0.13ωand 0.3ω.The AB s extend to 60°for the TE waves and 80.4°for the TM waves.There also exists a narrow frequency band in a lower frequency range.The relevant factors,which include the external temperature,the magnetic fields applied to the YIGF,the refractive index of the impedance matching layer,and the defect thickness,are adjusted to investigate the effects on the ABs.All the numerical simulations are based on the transfer matrix method.This work provides an approach to designs of isolators and so on.
基金supported by the National Natural Science Foundation of China(No.51902101)the Youth Natural Science Foundation of Hunan Province(No.2021JJ40044)+2 种基金Natural Science Foundation of Jiangsu Province(No.BK20201381)Science Foundation of Nanjing University of Posts and Telecommunications(Nos.NY219144 and NY221046)the National College Student Innovation and Entrepreneurship Training Program(No.202210293171K).
文摘Electrochemical gas evolution reactions are common but essential in many electrochemical processes including water electrolysis.During these processes,gas bubbles are constantly nucleating on reaction interfaces in electrolyte and consequently exert an impact on catalysts and the performance.In the past few decades,extensive studies have been conducted to characterize bubbles with emerging advanced technologies,manage behaviors of bubbles,and apply bubbles to various domains.In this review,we summarize representative discoveries as well as recent advancements in electrochemical gas evolution reactions from the perspective of gas bubbles.Finally,we end up this review with a profound outlook on future research topics from the combination of experiments and theoretical techniques,non-negligible bubble effects,gravity-free situation,and reactions under practical industrial conditions.
基金supported by the National Natural Science Foundation of China(Grant Nos.11974189,12175106,and 92365110)Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX23-1027)。
文摘Hyperentanglement, the simultaneous entanglement in more than one degree of freedom(DOF), plays an important role in quantum communication and quantum information processing for it can effectively increase the channel capacity. Existing hyperentanglement sources mainly focus on the generation of the hyperentanglement in two DOFs. In this paper, we design the generation protocols for three kinds of hyperentanglement encoded in three DOFs with the practical coherent pulses sources, including the polarization-frequency-space hyperentanglement, the polarization-frequency-time-bin hyperentanglement, and the polarizationspace-time-bin hyperentanglement. These protocols exploit the spontaneous parametric down-conversion(SPDC) process and the Sagnac interferometer. The three protocols are all based on feasible experimental condition and may have potential applications in future hyperentanglement-based quantum communication and quantum information processing protocols.
基金financial support from the National Natural Science Foundation of China(Grant No.22105106)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20210603)+1 种基金Nanjing Science and Technology Innovation Project for Overseas Students(Grant No.NJKCZYZZ2022-05)Start-up Funding from NUPTSF(Grant No.NY221003)。
文摘The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power density,and good safety,are considered ideal candidates.Nevertheless,the relatively low energy density restricts their practical applications.With a large dielectric constant of 18-46,Ta_(2)O_(5)-based materials typically exhibit excellent electron-binding ability,which is critical for enhancing the energy density of supercapacitors.In this work,the free-standingβ-Ta_(2)O_(5)/single-walled carbon nanotubes(SWCNTs)composite film was prepared,with a highβ-Ta_(2)O_(5)loading of over 70%.By anchoringβ-Ta_(2)O_(5)nanoparticles onto the surface of SWCNTs,the system’s flexibility and conductivity were significantly enhanced,which also facilitated the intercalation electrodynamics of metal cations.As a result,the flexibleβ-Ta_(2)O_(5)/SWCNTs film exhibits excellent Li-ion storage performance,with a high volumetric specific capacitance of 392.3 F cm^(-3)at the scan rate of 10 mV s^(-1)and 198.9 F cm^(-3)at 500 mV s^(-1).In addition,the asymmetric device,assembled by theβ-Ta_(2)O_(5)/SWCNTs and activated carbon films,shows a high energy density of 45.5 Wh kg^(-1)at the power density of 10.8 kW kg^(-1).This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.
基金supported by the National Key Research and Development Program of China(No.2021YFA1202000)the National Natural Science Foundation of China(Nos.52003115,62175102)+4 种基金the Natural Science Foundation of Jiangsu Province,Major Project(No.BK20212004)the Natural Science Foundation of Jiangsu Province(No.BK20200320)Program for Innovative Talents and Entrepreneurs in Jiangsu(No.JSSCTD202138)the Innovation and Entrepreneurship Program of Jiangsu Provincethe Start-up Fund at the Nanjing University(No.14912226).
文摘Self-assembled architectures of soft matter have fascinated scientists for centuries due to their unique physical properties originated from controllable orientational and/or positional orders,and diverse optic and photonic applications.If one could know how to design,fabricate,and manipulate these optical microstructures in soft matter systems,such as liquid crystals(LCs),that would open new opportunities in both scientific research and practical applications,such as the interaction between light and soft matter,the intrinsic assembly of the topological patterns,and the multidimensional control of the light(polarization,phase,spatial distribution,propagation direction).Here,we summarize recent progresses in self-assembled optical architectures in typical thermotropic LCs and bio-based lyotropic LCs.After briefly introducing the basic definitions and properties of the materials,we present the manipulation schemes of various LC microstructures,especially the topological and topographic configurations.This work further illustrates external-stimuli-enabled dynamic controllability of self-assembled optical structures of these soft materials,and demonstrates several emerging applications.Lastly,we discuss the challenges and opportunities of these materials towards soft matter photonics,and envision future perspectives in this field.
基金supported by the National Funds for Distinguished Young Scientists(No.61825503)the National Natural Science Foundation of China(Nos.51902101,61775101,and 61804082)+2 种基金the Natural Science Foundation of Jiangsu Province(Nos.BK20201381 and BK20210577)the Science Foundation of Nanjing University of Posts and Telecommunications(No.NY219144)the National College Student Innovation and Entrepreneurship Training Program.
文摘Heteroatom doping is a promising approach to enhance catalytic activity by modulating physical properties,electronic structure,and reaction pathway.Herein,we demonstrate that appropriate Ni-doping could trigger a preferential transition of the basal plane from 2H(trigonal prismatic)to 1T′(clustered Mo)by inducing lattice distortion and S vacancy(SV)and thus dramatically facilitate its catalytic hydrogen evolution activity.It is noteworthy that the unique catalysts did possess superior catalytic performance of hydrogen evolution reaction(HER).The rate of photocatalytic hydrogen evolution could reach 20.45 mmol·g^(−1)·h^(−1) and reduced only slightly in the long period of the photocatalytic process.First-principles calculations reveal that the distorted Ni-1T′-MoS_(2) with SV could generate favorable water adsorption energy(Ead(H_(2)O))and Gibbs free energy of hydrogen adsorption(∆GH).This work exhibits a facile and promising pathway for synergistically regulating physical properties,electronic structure,or wettability based on the doping strategy for designing HER electrocatalysts.
