The quantum phase transition between Z_(2) plaquette valence bound solid(PVBS) and superfluid(SF) phases on the planar pyrochlore lattice(square ice) is under debate. To gain further insight, here, we focus on the dyn...The quantum phase transition between Z_(2) plaquette valence bound solid(PVBS) and superfluid(SF) phases on the planar pyrochlore lattice(square ice) is under debate. To gain further insight, here, we focus on the dynamical features of the hard-core Bose–Hubbard model on this lattice and study the excitation spectra by combining stochastic analytic continuation and quantum Monte Carlo simulation. In both PVBS and SF phases,a flat band with bow-tie structure is observed and can be explained by certain symmetries. At the transition point,the spectra turn to be continuous and gapless. A(2+1)-dimensional Abelian–Higgs model with mixed 't Hooft anomaly is proposed to describe the transition, where the anomaly matching predicts that the deconfinement can exist on the domain walls. From the snapshot of the spin configuration in real space, we found the existence of the domain wall. We also found that the spectrum along a specific path in momentum space from PVBS phase to the transition point can be well described by an XXZ spin chain, and the critical theory of XXZ spin chain matches the anomaly. The two-spinon continuum along this specific path implies additional domain walls(point defect) can emerge in the domain walls(line defect) and take the role of deconfinement at the transition point.展开更多
A graph G is called d-degenerate if every subgraph of G has a vertex of degree at most d.It was known that planar graphs are 5-degenerate and every planar graph without k-cycles for some prescribed k∈{3,5,6}is 3-dege...A graph G is called d-degenerate if every subgraph of G has a vertex of degree at most d.It was known that planar graphs are 5-degenerate and every planar graph without k-cycles for some prescribed k∈{3,5,6}is 3-degenerate.In this paper,we show that if G is a planar graph without kites and 9-or 10-cycles,then G is 3-degenerate,hence 4-choosable and list vertex 2-arborable.展开更多
DP-coloring as a generalization of list coloring was introduced recently by Dvo˘r´ak and Postle.In this paper,we show that planar graphs without 5-cycles adjacent to two triangles are DP-4-colorable,which improve...DP-coloring as a generalization of list coloring was introduced recently by Dvo˘r´ak and Postle.In this paper,we show that planar graphs without 5-cycles adjacent to two triangles are DP-4-colorable,which improves the results of[Discrete Math.,2018,341(7):1983–1986]and[Discrete Appl.Math.,2020,277:245–251].展开更多
The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this is...The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this issue by leveraging screen-printing technology to fabricate high-performance PMSCs using innovative composite ink.The ink,a synergistic blend of few-layer graphene(Gt),carbon black(CB),and NiCo_(2)O_(4),was meticulously mixed to form a conductive and robust coating that enhanced the capacitive performance of the PMSCs.The optimized ink formulation and printing process result in a micro-supercapacitor with an exceptional areal capacitance of 18.95 mF/cm^(2)and an areal energy density of 2.63μW·h/cm^(2)at a current density of 0.05 mA/cm^(2),along with an areal power density of 0.025 mW/cm^(2).The devices demonstrated impressive durability with a capacitance retention rate of 94.7%after a stringent 20000-cycle test,demonstrating their potential for long-term applications.Moreover,the PMSCs displayed excellent mechanical flexibility,with a capacitance decrease of only 3.43%after 5000 bending cycles,highlighting their suitability for flexible electronic devices.The ease of integrating these PMSCs into series and parallel configurations for customized power further underscores their practicality for integrated power supply solutions in various technologies.展开更多
Planar chiral cyclophanes are a type of structurally intriguing organic molecules,which have found increasingly applications in the field of biologically active compounds,asymmetric catalysis,and optically pure materi...Planar chiral cyclophanes are a type of structurally intriguing organic molecules,which have found increasingly applications in the field of biologically active compounds,asymmetric catalysis,and optically pure materials.As such,significant efforts in the development of new methods to build up enantioenriched cyclophanes in a precise manner have attracted increased attention in recent years.Among the plethora of reported synthetic strategies,catalytic enantioselective method has emerged as one of the most straightforward and efficient ways to deliver optically pure planar chiral cyclophanes.In this review,the recent progress in catalytic enantioselective reactions for the synthesis of planar chiral cyclophanes will be discussed,which would stimulate the research interest of chemists for the discovery of novel asymmetric strategies for the preparation of valuable and previously difficult-to-access chiral molecules.展开更多
Multispectral imaging plays a crucial role in simultaneously capturing detailed spatial and spectral information,which is fundamental for understanding complex phenomena across various domains.Traditional systems face...Multispectral imaging plays a crucial role in simultaneously capturing detailed spatial and spectral information,which is fundamental for understanding complex phenomena across various domains.Traditional systems face significant challenges,such as large volume,static function,and limited wavelength selectivity.Here,we propose an innovative dynamic reflective multispectral imaging system via a thermally responsive cholesteric liquid crystal based planar lens.By employing advanced photoalignment technology,the phase distribution of a lens is imprinted to the liquid crystal director.The reflection band is reversibly tuned from 450 nm to 750 nm by thermally controlling the helical pitch of the cholesteric liquid crystal,allowing selectively capturing images in different colors.This capability increases imaging versatility,showing great potential in precision agriculture for assessing crop health,noninvasive diagnostics in healthcare,and advanced remote sensing for environmental monitoring.展开更多
In this paper,a 4×4 wideband linearly po-larization(LP)antenna array is proposed by using pla-nar dual-arm spiral structures.Wideband balun struc-tures,composed of microstrip line-fed coupling slots,are adopted t...In this paper,a 4×4 wideband linearly po-larization(LP)antenna array is proposed by using pla-nar dual-arm spiral structures.Wideband balun struc-tures,composed of microstrip line-fed coupling slots,are adopted to feed two dual-arms spiral structures with opposite phases.Then,by combining the left-and right-hand circular polarizations,a linearly polar-ization is achieved.The proposed antenna has a wide operating bandwidth due to the wideband nature of the spiral structure.Simulated results show that the an-tenna element can achieve a 68.73%impedance band-width and a maximum gain of 6.64 dBi within 19.44–38.83 GHz.A 4×4 array prototype is designed to verify the concept.Measured results show that an impedance bandwidth of 63.73%is obtained.The pro-posed array has the merits of a wide bandwidth,a low profile,a low cost,and a small size,which is promis-ing for the application in millimeter wave wireless sys-tems.展开更多
Pursuing new two-dimensional(2D)materials has been a hot topic in materials science,driven by their potential for diverse applications.Recent research has unveiled stable planar hypercoordinate motifs with unconventio...Pursuing new two-dimensional(2D)materials has been a hot topic in materials science,driven by their potential for diverse applications.Recent research has unveiled stable planar hypercoordinate motifs with unconventional geometric arrangements and bonding patterns that facilitate the synthesis of new 2D materials with diverse applications.Among these,yet the design of 2D transition metal systems featuring planar pentacoordinate boron(ppB)is particularly intriguing.Here we address this gap by proposing a novel family of transition metal boride monolayers(MBenes)composed of ppB and heptacoordinate M motifs.The novelty of our MBenes stems from their distinct atomic arrangements and bonding configurations,setting them apart from traditional 2D materials.High-throughput calculations identified 10 stable MBenes(with the stoichiometry of MB,M=Cr,Fe,Co,Ni,Cu,Mo,Pd,Ag,Pt,Au)with exceptional thermodynamic,dynamic,thermal,and mechanical stabilities attributed to strong BB covalent bonds and MB ionic interactions.Notably,five of these MBenes(M=Ni,Pd,Pt,Ag,Au)hold high promise as topological superconducting materials with superconducting transition temperatures of 2.4-5.2 K.This discovery not only enriches the family of topological superconducting materials but also opens new avenues for quantum device development.Meanwhile,FeB monolayer exhibits robust ferromagnetic properties with a high Curie temperature of~750 K,which is particularly significant for spintronics applications.In addition,NiB and CuB MBenes demonstrate extremely low sodium diffusion barriers(about 30 and 90 meV)and high sodium storage capacities(788 and 734 mAh g1,respectively),making them promising anode materials for sodium-ion batteries(SIBs).This study expands the selection of electrode materials for SIBs and mitigates some existing limitations in battery technology.Overall,these findings underscore the multifunctional potential of MBenes,positioning them as transformative materials for quantum computing,spintronics,and energy storage applications.展开更多
Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose...Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose significant limitations on capacity expansion,often requiring physical replacement and causing service disruptions.Thermally tunable optical splitters address this challenge by enabling adjustable splitting ratios,but their operation is contingent upon a continuous power supply and complex driving systems.In this work,we present a novel,non-volatile tunable PLC platform based on Sb_(2)S_(3)phase-change materials.The proposed device,which incor-porates a Mach-Zehnder interferometer(MZI)optical switch structure,offers tunable splitting ratios via laser-direct writing or ohmic heating,providing flexible reconfiguration capabilities.Experimental results demonstrate non-volatile power splitting ranging from 50∶50 to 20∶80,with a modest increase of approximately 1 dB in additional loss.This work highlights the potential of the proposed platform for low-power,high-efficiency,and reconfigurable photonic networks.展开更多
Diffractive optical neural networks(DONNs)have exhibited the advantages of parallelization,high speed,and low consumption.However,the existing DONNs based on free-space diffractive optical elements are bulky and unste...Diffractive optical neural networks(DONNs)have exhibited the advantages of parallelization,high speed,and low consumption.However,the existing DONNs based on free-space diffractive optical elements are bulky and unsteady.In this study,we propose a planar-waveguide integrated diffractive neural network chip architecture.The three diffractive layers are engraved on the same side of a quartz wafer.The three-layer chip is designed with 32-mm3 processing space and enables a computing speed of 3.1×109 Tera operations per second.The results show that the proposed chip achieves 73.4%experimental accuracy for the Modified National Institute of Standards and Technology database while showing the system’s robustness in a cycle test.The consistency of experiments is 88.6%,and the arithmetic mean standard deviation of the results is~4.7%.The proposed chip architecture can potentially revolutionize high-resolution optical processing tasks with high robustness.展开更多
Radio antenna arrays have many advantages for astronomical observations,such as high resolution,high sensitivity,multi-target simultaneous observation,and flexible beam formation.Problems surrounding key indices,such ...Radio antenna arrays have many advantages for astronomical observations,such as high resolution,high sensitivity,multi-target simultaneous observation,and flexible beam formation.Problems surrounding key indices,such as sensitivity enhancement,scanning range extension,and sidelobe level suppression,need to be solved urgently.Here,we propose a sparse optimization scheme based on a genetic algorithm for a 64-array element planar radio antenna array.As optimization targets for the iterative process of the genetic algorithm,we use the maximum sidelobe levels and beamwidth of multiple cross-section patterns that pass through the main beam in three-dimensions,with the maximum sidelobe levels of the patterns at several different scanning angles.Element positions are adjusted for iterations,to select the optimal array configuration.Following sparse layout optimization,the simulated 64-element planar radio antenna array shows that the maximum sidelobe level decreases by 1.79 dB,and the beamwidth narrows by 3°.Within the scan range of±30°,after sparse array optimization,all sidelobe levels decrease,and all beamwidths narrow.This performance improvement can potentially enhance the sensitivity and spatial resolution of radio telescope systems.展开更多
We systematically investigate the planar transport properties of the two-dimensional layered compound GaGeTe. The results reveal distinct anisotropies in both the longitudinal and planar Hall resistances as the magnet...We systematically investigate the planar transport properties of the two-dimensional layered compound GaGeTe. The results reveal distinct anisotropies in both the longitudinal and planar Hall resistances as the magnetic field is rotated within the plane, which are well-captured by the planar Hall effect(PHE) model. Further analysis indicates that the primary contribution to the PHE in GaGeTe arises from its ferromagnetic component and anisotropic orbital resistance, rather than topologically nontrivial chiral anomaly. This work deepens our understanding of the PHE mechanism and offers valuable insights for the development of planar Hall sensors based on two-dimensional materials.展开更多
To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement ...To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement of CPL,they are not combined together to boost CPL.Here,a new tetraphenylethylene(TPE)tetracycle acid helicate bearing both helical chirality and planar chirality was designed and synthesized.Uniquely,synergy of the helical chirality and planar chirality was used to boost CPL signals both in solution and in helical self-assemblies.In the presence of octadecylamine,the TPE helicate could form helical nanofibers that emitted strong CPL signals with an absolute g_(lum)value up to 0.237.Exceptionally,followed by addition of para-phenylenediamine,the g_(lum)value was successively increased to 0.387 due to formation of bigger helical nanofibers.Compared with that of TPE helicate itself,the CPL signal of the self-assemblies was not only magnified by 104-fold but also inversed,which was very rare result for CPL-active materials.Surprisingly,the interaction of TPE helicate with xylylenediamine even gave a gel,which was transformed into suspension by shaking.Unexpectedly,the suspension showed 40-fold stronger CPL signals than the gel with signal direction inversion each other.Using synergy of the helical chirality and planar chirality to significantly boost CPL intensity provides a new strategy in preparation of organic CPL materials having very large g_(lum)value.展开更多
In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),fo...In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),followed with a ZnS layer grown by the chemical vapor deposition(CVD).The p-type contact layer was constructed by thermal diffusion in the undoped superlattices.The Zinc atom was successfully realised into the superlattice and a PπMN T2SL structure was con-structed.Furthermore,the effects of different diffusion temperatures on the dark current performance of the devices were researched.The 50%cut-off wavelength of the photodetector is 5.26μm at 77 K with 0 V bias.The minimum dark current density is 8.67×10^(−5) A/cm^(2) and the maximum quantum efficiency of 42.5%,and the maximum detectivity reaches 3.90×10^(10) cm·Hz^(1/2)/W at 77 K.The 640×512 focal plane arrays(FPA)based on the planner junction were fabricated afterwards.The FPA achieves a noise equivalent temperature difference(NETD)of 539 mK.展开更多
Quantum error correction is essential for realizing fault-tolerant quantum computing,where both the efficiency and accuracy of the decoding algorithms play critical roles.In this work,we introduce the implementation o...Quantum error correction is essential for realizing fault-tolerant quantum computing,where both the efficiency and accuracy of the decoding algorithms play critical roles.In this work,we introduce the implementation of the PLANAR algorithm,a software framework designed for fast and exact decoding of quantum codes with a planar structure.The algorithm first converts the optimal decoding of quantum codes into a partition function computation problem of an Ising spin glass model.Then it utilizes the exact Kac–Ward formula to solve it.In this way,PLANAR offers the exact maximum likelihood decoding in polynomial complexity for quantum codes with a planar structure,including the surface code with independent code-capacity noise and the quantum repetition code with circuit-level noise.Unlike traditional minimumweight decoders such as minimum-weight perfect matching(MWPM),PLANAR achieves theoretically optimal performance while maintaining polynomial-time efficiency.In addition,to demonstrate its capabilities,we exemplify the implementation using the rotated surface code,a commonly used quantum error correction code with a planar structure,and show that PLANAR achieves a threshold of approximately p_(uc)≈0.109 under the depolarizing error model,with a time complexity scaling of O(N^(0.69)),where N is the number of spins in the Ising model.展开更多
The Görtler vortex is a characteristic flow feature observed in the boundary layer on compression ramp in hypersonic flow.In the context of high-enthalpy plasma flows during aerospace re-entry processes,there is ...The Görtler vortex is a characteristic flow feature observed in the boundary layer on compression ramp in hypersonic flow.In the context of high-enthalpy plasma flows during aerospace re-entry processes,there is currently a lack of effective means to visualize the boundary layer.In this study,the Nitric Oxide Planar Laser-Induced Fluorescence(NO-PLIF)technique was employed to visualize the boundary layer of a compression ramp in a 50-MW arc-heated plasma wind tunnel.Görtler-like vortex structures were observed in the boundary layer of the ramp.This is the first time that Görtler vortices have been clearly observed in a high-enthalpy plasma flow.By varying the flow conditions,the Görtler vortices persisted in the boundary layer of the ramp when the total enthalpy of the arc-heated wind tunnel exceeded 12.3 MJ/kg.Several image processing techniques were applied to extract the structure of high-speed Görtler streaks,and the position of the high-speed streaks was found to be non-fixed,whereas the average Görtler wavelength remained at approximately 30 mm at a 10°ramp and showed limited variation with the total enthalpy.Additionally,a sheet-forming optics system with an adjustable angle and height was designed to enable visualization of the Görtler vortices in the boundary layer of the ramp at different angles and heights.The vortices on the low-angle ramp exhibited better stability and shorter wavelengths.Visualization results at different heights confirmed that the Görtler vortex wavelength was approximately twice the boundary layer thickness.This study demonstrates the feasibility and potential of the PLIF technique for the visualization of the boundary layer in plasma flows,especially with regard to Görtler vortices.展开更多
We present a compact cold atom platform where an optical grating chip and planar coil chip are placed inside a compact vacuum chamber to create a magneto-optical trap.This approach significantly reduces the system vol...We present a compact cold atom platform where an optical grating chip and planar coil chip are placed inside a compact vacuum chamber to create a magneto-optical trap.This approach significantly reduces the system volume to about 20×20×20 cm^(3) compared to conventional vacuum systems and offers greater flexibility in accessing the trapped atoms.We demonstrate the trapping of 3×10^(5) cold rubidium atoms at a temperature of 100μK in a vacuum pressure below 10^(−7) mbar.The simplified optical geometry,low power consumption,and high degree of integration make this a promising platform for portable and versatile cold-atom devices in quantum sensing,timing,and information processing.展开更多
Two-dimensional(2D)transition metal dichalcogenides(TMDs),which allow atomic-scale manipulation,have supe-rior electrical and optical properties that challenge the limits of traditional bulk semiconductors like silico...Two-dimensional(2D)transition metal dichalcogenides(TMDs),which allow atomic-scale manipulation,have supe-rior electrical and optical properties that challenge the limits of traditional bulk semiconductors like silicon^([1,2]).As a repre-sentative TMD and a promising 2D channel material for high-performance,scalable p-type transistors,tungsten diselenide(WSe_(2))has attracted considerable academic and industrial interest for its potential in advanced complementary metal−oxide−semiconductor(CMOS)logic technology and in extending Moore’s Law^([3−7]).展开更多
Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancemen...Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancement of planaroptics has promoted the development of compact MOTs. In this article, we review the development of compact MOTs basedon planar optics. First, we introduce the standardMOTs. We then introduce the gratingMOTs with micron structures, whichhave been used to build cold atomic clocks, cold atomic interferometers, and ultra-cold sources. Further, we introducethe integrated MOTs based on nano-scale metasurfaces. These new compact MOTs greatly reduce volume and powerconsumption, and provide new opportunities for fundamental research and practical applications.展开更多
基金supported by the start-up funding of CQNU (Grant No. 24XLB010)supported by the Science and Technology Research Program of Chongqing Municipal Education Commission (Grant No. KJQN202100514)+3 种基金funding from Chongqing Natural Science Foundation under Grant No. CSTB2022NSCQ-JQX0018the Fundamental Research Funds for the Central Universities Grant No. 2021CDJZYJH-003Xiaomi Foundation/Xiaomi Young Talents Programfunding from the National Science Foundation of China under Grant Nos. 12404169, 12147172, 12274046, 11874094, 12147102, and 12347101。
文摘The quantum phase transition between Z_(2) plaquette valence bound solid(PVBS) and superfluid(SF) phases on the planar pyrochlore lattice(square ice) is under debate. To gain further insight, here, we focus on the dynamical features of the hard-core Bose–Hubbard model on this lattice and study the excitation spectra by combining stochastic analytic continuation and quantum Monte Carlo simulation. In both PVBS and SF phases,a flat band with bow-tie structure is observed and can be explained by certain symmetries. At the transition point,the spectra turn to be continuous and gapless. A(2+1)-dimensional Abelian–Higgs model with mixed 't Hooft anomaly is proposed to describe the transition, where the anomaly matching predicts that the deconfinement can exist on the domain walls. From the snapshot of the spin configuration in real space, we found the existence of the domain wall. We also found that the spectrum along a specific path in momentum space from PVBS phase to the transition point can be well described by an XXZ spin chain, and the critical theory of XXZ spin chain matches the anomaly. The two-spinon continuum along this specific path implies additional domain walls(point defect) can emerge in the domain walls(line defect) and take the role of deconfinement at the transition point.
文摘A graph G is called d-degenerate if every subgraph of G has a vertex of degree at most d.It was known that planar graphs are 5-degenerate and every planar graph without k-cycles for some prescribed k∈{3,5,6}is 3-degenerate.In this paper,we show that if G is a planar graph without kites and 9-or 10-cycles,then G is 3-degenerate,hence 4-choosable and list vertex 2-arborable.
基金Partially supported by NSFC(No.12301436)NSF of Guangxi Province(No.2025GXNSFAA069811)。
文摘DP-coloring as a generalization of list coloring was introduced recently by Dvo˘r´ak and Postle.In this paper,we show that planar graphs without 5-cycles adjacent to two triangles are DP-4-colorable,which improves the results of[Discrete Math.,2018,341(7):1983–1986]and[Discrete Appl.Math.,2020,277:245–251].
文摘In this paper,by using the method of Lyapunov-Schmidt reduction,we obtain the existence of multi-bump solutions for planar Schrödinger-Poisson system.
基金supported by the Shanxi Province Central Guidance Fund for Local Science and Technology Development Project(YDZJSX2024D030)the National Natural Science Foundation of China(22075197,22278290)+2 种基金the Shanxi Province Key Research and Development Program Project(2021020660301013)the Shanxi Provincial Natural Science Foundation of China(202103021224079)the Research and Development Project of Key Core and Common Technology of Shanxi Province(20201102018).
文摘The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this issue by leveraging screen-printing technology to fabricate high-performance PMSCs using innovative composite ink.The ink,a synergistic blend of few-layer graphene(Gt),carbon black(CB),and NiCo_(2)O_(4),was meticulously mixed to form a conductive and robust coating that enhanced the capacitive performance of the PMSCs.The optimized ink formulation and printing process result in a micro-supercapacitor with an exceptional areal capacitance of 18.95 mF/cm^(2)and an areal energy density of 2.63μW·h/cm^(2)at a current density of 0.05 mA/cm^(2),along with an areal power density of 0.025 mW/cm^(2).The devices demonstrated impressive durability with a capacitance retention rate of 94.7%after a stringent 20000-cycle test,demonstrating their potential for long-term applications.Moreover,the PMSCs displayed excellent mechanical flexibility,with a capacitance decrease of only 3.43%after 5000 bending cycles,highlighting their suitability for flexible electronic devices.The ease of integrating these PMSCs into series and parallel configurations for customized power further underscores their practicality for integrated power supply solutions in various technologies.
基金financial support provided by Huanghuai University and Hangzhou Medical College.
文摘Planar chiral cyclophanes are a type of structurally intriguing organic molecules,which have found increasingly applications in the field of biologically active compounds,asymmetric catalysis,and optically pure materials.As such,significant efforts in the development of new methods to build up enantioenriched cyclophanes in a precise manner have attracted increased attention in recent years.Among the plethora of reported synthetic strategies,catalytic enantioselective method has emerged as one of the most straightforward and efficient ways to deliver optically pure planar chiral cyclophanes.In this review,the recent progress in catalytic enantioselective reactions for the synthesis of planar chiral cyclophanes will be discussed,which would stimulate the research interest of chemists for the discovery of novel asymmetric strategies for the preparation of valuable and previously difficult-to-access chiral molecules.
基金supported by the National Key Research and Development Program of China(No.2022YFA1203700)the National Natural Science Foundation of China(NSFC)(Nos.62405129 and 62035008)+1 种基金the University Research Project of Guangzhou Education Bureau(No.202235053)the Natural Science Foundation of Jiangsu Province(No.BK20241197).
文摘Multispectral imaging plays a crucial role in simultaneously capturing detailed spatial and spectral information,which is fundamental for understanding complex phenomena across various domains.Traditional systems face significant challenges,such as large volume,static function,and limited wavelength selectivity.Here,we propose an innovative dynamic reflective multispectral imaging system via a thermally responsive cholesteric liquid crystal based planar lens.By employing advanced photoalignment technology,the phase distribution of a lens is imprinted to the liquid crystal director.The reflection band is reversibly tuned from 450 nm to 750 nm by thermally controlling the helical pitch of the cholesteric liquid crystal,allowing selectively capturing images in different colors.This capability increases imaging versatility,showing great potential in precision agriculture for assessing crop health,noninvasive diagnostics in healthcare,and advanced remote sensing for environmental monitoring.
基金supported in part by the National Natural Science Foundation of China under Grant 62131008the Fundamental Research Funds for the Central Universities 2242022k60003.
文摘In this paper,a 4×4 wideband linearly po-larization(LP)antenna array is proposed by using pla-nar dual-arm spiral structures.Wideband balun struc-tures,composed of microstrip line-fed coupling slots,are adopted to feed two dual-arms spiral structures with opposite phases.Then,by combining the left-and right-hand circular polarizations,a linearly polar-ization is achieved.The proposed antenna has a wide operating bandwidth due to the wideband nature of the spiral structure.Simulated results show that the an-tenna element can achieve a 68.73%impedance band-width and a maximum gain of 6.64 dBi within 19.44–38.83 GHz.A 4×4 array prototype is designed to verify the concept.Measured results show that an impedance bandwidth of 63.73%is obtained.The pro-posed array has the merits of a wide bandwidth,a low profile,a low cost,and a small size,which is promis-ing for the application in millimeter wave wireless sys-tems.
基金supported by Research Foundation for Advanced Talents of Inner Mongolia Normal University(2025YJRC005)the National Natural Science Foundation of China(12364038)+5 种基金the“Grassland Talents”project of the Inner Mongolia Autonomous Region(12000-12102613)the Young Science and Technology Talents Cultivation Project of Inner Mongolia University(21200-5223708)the Industrial Technology Innovation Projects of Inner Mongolia Academy of Science and Technology of China(2023JSYD01002)Science and Technology Plan Projects of Inner Mongolia Autonomous Region of China(2023KYPT0012)Key Project Funding from the Inner Mongolia Autonomous Region Natural Science Foundation(2023ZD27)High Level Introduction of Talent Research Start-up Fund(5909002405).
文摘Pursuing new two-dimensional(2D)materials has been a hot topic in materials science,driven by their potential for diverse applications.Recent research has unveiled stable planar hypercoordinate motifs with unconventional geometric arrangements and bonding patterns that facilitate the synthesis of new 2D materials with diverse applications.Among these,yet the design of 2D transition metal systems featuring planar pentacoordinate boron(ppB)is particularly intriguing.Here we address this gap by proposing a novel family of transition metal boride monolayers(MBenes)composed of ppB and heptacoordinate M motifs.The novelty of our MBenes stems from their distinct atomic arrangements and bonding configurations,setting them apart from traditional 2D materials.High-throughput calculations identified 10 stable MBenes(with the stoichiometry of MB,M=Cr,Fe,Co,Ni,Cu,Mo,Pd,Ag,Pt,Au)with exceptional thermodynamic,dynamic,thermal,and mechanical stabilities attributed to strong BB covalent bonds and MB ionic interactions.Notably,five of these MBenes(M=Ni,Pd,Pt,Ag,Au)hold high promise as topological superconducting materials with superconducting transition temperatures of 2.4-5.2 K.This discovery not only enriches the family of topological superconducting materials but also opens new avenues for quantum device development.Meanwhile,FeB monolayer exhibits robust ferromagnetic properties with a high Curie temperature of~750 K,which is particularly significant for spintronics applications.In addition,NiB and CuB MBenes demonstrate extremely low sodium diffusion barriers(about 30 and 90 meV)and high sodium storage capacities(788 and 734 mAh g1,respectively),making them promising anode materials for sodium-ion batteries(SIBs).This study expands the selection of electrode materials for SIBs and mitigates some existing limitations in battery technology.Overall,these findings underscore the multifunctional potential of MBenes,positioning them as transformative materials for quantum computing,spintronics,and energy storage applications.
基金sponsored by the National Key Research and Development Program of China(2020YFA0714504,2019YFA0709100)the program of the National Natural Science Foundation of China(U24A20309,62305043).
文摘Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose significant limitations on capacity expansion,often requiring physical replacement and causing service disruptions.Thermally tunable optical splitters address this challenge by enabling adjustable splitting ratios,but their operation is contingent upon a continuous power supply and complex driving systems.In this work,we present a novel,non-volatile tunable PLC platform based on Sb_(2)S_(3)phase-change materials.The proposed device,which incor-porates a Mach-Zehnder interferometer(MZI)optical switch structure,offers tunable splitting ratios via laser-direct writing or ohmic heating,providing flexible reconfiguration capabilities.Experimental results demonstrate non-volatile power splitting ranging from 50∶50 to 20∶80,with a modest increase of approximately 1 dB in additional loss.This work highlights the potential of the proposed platform for low-power,high-efficiency,and reconfigurable photonic networks.
基金supported by the National Natural Science Foundation of China(Grant Nos.62175050 and U2341245)the Fundamental Research Funds for the Central Universities(Grant No.HIT.OCEF.2024054).
文摘Diffractive optical neural networks(DONNs)have exhibited the advantages of parallelization,high speed,and low consumption.However,the existing DONNs based on free-space diffractive optical elements are bulky and unsteady.In this study,we propose a planar-waveguide integrated diffractive neural network chip architecture.The three diffractive layers are engraved on the same side of a quartz wafer.The three-layer chip is designed with 32-mm3 processing space and enables a computing speed of 3.1×109 Tera operations per second.The results show that the proposed chip achieves 73.4%experimental accuracy for the Modified National Institute of Standards and Technology database while showing the system’s robustness in a cycle test.The consistency of experiments is 88.6%,and the arithmetic mean standard deviation of the results is~4.7%.The proposed chip architecture can potentially revolutionize high-resolution optical processing tasks with high robustness.
基金supported by the Ministry of Science and Technology SKA Special Project(2020SKA0110202)the Special Project on Building a Science and Technology Innovation Center for South and Southeast Asia–International Joint Innovation Platform in Yunnan Province:"Yunnan Sino-Malaysian International Joint Laboratory of HF-VHF Advanced Radio Astronomy Technology"(202303AP140003)+4 种基金the National Natural Science Foundation of China (NSFC) Joint Fund for Astronomy (JFA) incubator program (U2031133)the International Partnership Program Project of the International Cooperation Bureau of the Chinese Academy of Sciences:"Belt and Road"Cooperation (114A11KYSB20200001)the Kunming Foreign (International) Cooperation Base Program:"Yunnan Observatory of the Chinese Academy of Sciences-University of Malaya Joint R&D Cooperation Base for Advanced Radio Astronomy Technology"(GHJD-2021022)the China-Malaysia Collaborative Research on Space Remote Sensing and Radio Astronomy Observation of Space Weather at Low and Middle Latitudes under the Key Special Project of the State Key R&D Program of the Ministry of Science and Technology for International Cooperation in Science,Technology and Innovation among Governments (2022YFE0140000)the High-precision calibration method for low-frequency radio interferometric arrays for the SKA project of the Ministry of Science and Technology(2020SKA0110300).
文摘Radio antenna arrays have many advantages for astronomical observations,such as high resolution,high sensitivity,multi-target simultaneous observation,and flexible beam formation.Problems surrounding key indices,such as sensitivity enhancement,scanning range extension,and sidelobe level suppression,need to be solved urgently.Here,we propose a sparse optimization scheme based on a genetic algorithm for a 64-array element planar radio antenna array.As optimization targets for the iterative process of the genetic algorithm,we use the maximum sidelobe levels and beamwidth of multiple cross-section patterns that pass through the main beam in three-dimensions,with the maximum sidelobe levels of the patterns at several different scanning angles.Element positions are adjusted for iterations,to select the optimal array configuration.Following sparse layout optimization,the simulated 64-element planar radio antenna array shows that the maximum sidelobe level decreases by 1.79 dB,and the beamwidth narrows by 3°.Within the scan range of±30°,after sparse array optimization,all sidelobe levels decrease,and all beamwidths narrow.This performance improvement can potentially enhance the sensitivity and spatial resolution of radio telescope systems.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2023YFA1406500)the National Natural Science Foundation of China (Grant Nos. U19A2093 and 11904002)+1 种基金the Excellent Youth Project of the Natural Science Foundation of Anhui Province, China (Grant No. 2308085Y07)the Anhui Provincial Major Science and Technology Project (Grant No. s202305a12020005)。
文摘We systematically investigate the planar transport properties of the two-dimensional layered compound GaGeTe. The results reveal distinct anisotropies in both the longitudinal and planar Hall resistances as the magnetic field is rotated within the plane, which are well-captured by the planar Hall effect(PHE) model. Further analysis indicates that the primary contribution to the PHE in GaGeTe arises from its ferromagnetic component and anisotropic orbital resistance, rather than topologically nontrivial chiral anomaly. This work deepens our understanding of the PHE mechanism and offers valuable insights for the development of planar Hall sensors based on two-dimensional materials.
基金National Natural Science Foundation of China(Nos.22072050,22372066 and 22301090)the Open Research Fund(No.2024JYBKF05)of Key Laboratory of Material Chemistry for Energy Conversion and Storage(HUST)Ministry of Educationthe China Postdoctoral Science Foundation(No.2023M731189)for financial support,and thank the Analytical and Testing Centre at Huazhong University of Science and Technology for measurement.
文摘To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement of CPL,they are not combined together to boost CPL.Here,a new tetraphenylethylene(TPE)tetracycle acid helicate bearing both helical chirality and planar chirality was designed and synthesized.Uniquely,synergy of the helical chirality and planar chirality was used to boost CPL signals both in solution and in helical self-assemblies.In the presence of octadecylamine,the TPE helicate could form helical nanofibers that emitted strong CPL signals with an absolute g_(lum)value up to 0.237.Exceptionally,followed by addition of para-phenylenediamine,the g_(lum)value was successively increased to 0.387 due to formation of bigger helical nanofibers.Compared with that of TPE helicate itself,the CPL signal of the self-assemblies was not only magnified by 104-fold but also inversed,which was very rare result for CPL-active materials.Surprisingly,the interaction of TPE helicate with xylylenediamine even gave a gel,which was transformed into suspension by shaking.Unexpectedly,the suspension showed 40-fold stronger CPL signals than the gel with signal direction inversion each other.Using synergy of the helical chirality and planar chirality to significantly boost CPL intensity provides a new strategy in preparation of organic CPL materials having very large g_(lum)value.
基金supported by the National Key Technologies R&D Program of China(Grant Nos.2024YFA1208904,2019YFA0705203)Major Program of the National Natural Science Foundation of China(Grant Nos.62004189,61274013)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0460000)the Research Foundation for Advanced Talents of the Chinese Academy of Sciences(Grant No.E27RBB03).
文摘In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),followed with a ZnS layer grown by the chemical vapor deposition(CVD).The p-type contact layer was constructed by thermal diffusion in the undoped superlattices.The Zinc atom was successfully realised into the superlattice and a PπMN T2SL structure was con-structed.Furthermore,the effects of different diffusion temperatures on the dark current performance of the devices were researched.The 50%cut-off wavelength of the photodetector is 5.26μm at 77 K with 0 V bias.The minimum dark current density is 8.67×10^(−5) A/cm^(2) and the maximum quantum efficiency of 42.5%,and the maximum detectivity reaches 3.90×10^(10) cm·Hz^(1/2)/W at 77 K.The 640×512 focal plane arrays(FPA)based on the planner junction were fabricated afterwards.The FPA achieves a noise equivalent temperature difference(NETD)of 539 mK.
基金supported by the National Natural Science Foundation of China(Grant Nos.12325501,12047503,and 12247104)the Chinese Academy of Sciences(Grant No.ZDRW-XX-2022-3-02)P.Z.is partially supported by the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301900).
文摘Quantum error correction is essential for realizing fault-tolerant quantum computing,where both the efficiency and accuracy of the decoding algorithms play critical roles.In this work,we introduce the implementation of the PLANAR algorithm,a software framework designed for fast and exact decoding of quantum codes with a planar structure.The algorithm first converts the optimal decoding of quantum codes into a partition function computation problem of an Ising spin glass model.Then it utilizes the exact Kac–Ward formula to solve it.In this way,PLANAR offers the exact maximum likelihood decoding in polynomial complexity for quantum codes with a planar structure,including the surface code with independent code-capacity noise and the quantum repetition code with circuit-level noise.Unlike traditional minimumweight decoders such as minimum-weight perfect matching(MWPM),PLANAR achieves theoretically optimal performance while maintaining polynomial-time efficiency.In addition,to demonstrate its capabilities,we exemplify the implementation using the rotated surface code,a commonly used quantum error correction code with a planar structure,and show that PLANAR achieves a threshold of approximately p_(uc)≈0.109 under the depolarizing error model,with a time complexity scaling of O(N^(0.69)),where N is the number of spins in the Ising model.
基金supported by the National Natural Science Foundation of China(Nos.62175053,62305087)。
文摘The Görtler vortex is a characteristic flow feature observed in the boundary layer on compression ramp in hypersonic flow.In the context of high-enthalpy plasma flows during aerospace re-entry processes,there is currently a lack of effective means to visualize the boundary layer.In this study,the Nitric Oxide Planar Laser-Induced Fluorescence(NO-PLIF)technique was employed to visualize the boundary layer of a compression ramp in a 50-MW arc-heated plasma wind tunnel.Görtler-like vortex structures were observed in the boundary layer of the ramp.This is the first time that Görtler vortices have been clearly observed in a high-enthalpy plasma flow.By varying the flow conditions,the Görtler vortices persisted in the boundary layer of the ramp when the total enthalpy of the arc-heated wind tunnel exceeded 12.3 MJ/kg.Several image processing techniques were applied to extract the structure of high-speed Görtler streaks,and the position of the high-speed streaks was found to be non-fixed,whereas the average Görtler wavelength remained at approximately 30 mm at a 10°ramp and showed limited variation with the total enthalpy.Additionally,a sheet-forming optics system with an adjustable angle and height was designed to enable visualization of the Görtler vortices in the boundary layer of the ramp at different angles and heights.The vortices on the low-angle ramp exhibited better stability and shorter wavelengths.Visualization results at different heights confirmed that the Görtler vortex wavelength was approximately twice the boundary layer thickness.This study demonstrates the feasibility and potential of the PLIF technique for the visualization of the boundary layer in plasma flows,especially with regard to Görtler vortices.
基金supported by the National Key R&D Program(Grant Nos.2021YFA1402004 and 2021YFF0603701)the National Natural Science Foundation of China(Grant Nos.12134014,U21A20433,U21A6006,and 92265108)+1 种基金the Fundamental Research Funds for the Central Universitiesthe University of Science and Technology of China(USTC)Research Funds of the Double First-Class Initiative。
文摘We present a compact cold atom platform where an optical grating chip and planar coil chip are placed inside a compact vacuum chamber to create a magneto-optical trap.This approach significantly reduces the system volume to about 20×20×20 cm^(3) compared to conventional vacuum systems and offers greater flexibility in accessing the trapped atoms.We demonstrate the trapping of 3×10^(5) cold rubidium atoms at a temperature of 100μK in a vacuum pressure below 10^(−7) mbar.The simplified optical geometry,low power consumption,and high degree of integration make this a promising platform for portable and versatile cold-atom devices in quantum sensing,timing,and information processing.
文摘Two-dimensional(2D)transition metal dichalcogenides(TMDs),which allow atomic-scale manipulation,have supe-rior electrical and optical properties that challenge the limits of traditional bulk semiconductors like silicon^([1,2]).As a repre-sentative TMD and a promising 2D channel material for high-performance,scalable p-type transistors,tungsten diselenide(WSe_(2))has attracted considerable academic and industrial interest for its potential in advanced complementary metal−oxide−semiconductor(CMOS)logic technology and in extending Moore’s Law^([3−7]).
基金the National Key Research and Development Program of China(Grant No.2022YFA1404104)the National Natural Science Foundation of China(Grant Nos.12025509 and 12104521)Fundamental Research Project of Shenzhen(Grant No.JCYJ20230808105009018).
文摘Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancement of planaroptics has promoted the development of compact MOTs. In this article, we review the development of compact MOTs basedon planar optics. First, we introduce the standardMOTs. We then introduce the gratingMOTs with micron structures, whichhave been used to build cold atomic clocks, cold atomic interferometers, and ultra-cold sources. Further, we introducethe integrated MOTs based on nano-scale metasurfaces. These new compact MOTs greatly reduce volume and powerconsumption, and provide new opportunities for fundamental research and practical applications.
