Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/ch...Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate geometries.We designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed materials.We employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate conditions.These techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow relaxation.Furthermore,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting bath.These insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral domains.Our biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.展开更多
Chirality(Greek“handiness”)is a property of many com-plex molecules.Chiral molecules exist in two forms,one being the mirror image of the other.Like for our hands,it is impossible to make the images identical by a s...Chirality(Greek“handiness”)is a property of many com-plex molecules.Chiral molecules exist in two forms,one being the mirror image of the other.Like for our hands,it is impossible to make the images identical by a suitable rota-tion.The two forms are called left-handed and right-handed.They have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a reflection.Other properties that are insensitive to the geometry are also the same.The different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same angle.However,the geometrical differences between the two species may have other conse-quences.The two species of the carvon molecule shown in Fig.1 taste quite differently.展开更多
The chiral 2×2 charge order has been reported and confirmed in the kagome superconductor RbV_(3)Sb_(5),while its interplay with superconductivity remains elusive owing to its lowest superconducting transition tem...The chiral 2×2 charge order has been reported and confirmed in the kagome superconductor RbV_(3)Sb_(5),while its interplay with superconductivity remains elusive owing to its lowest superconducting transition temperature Tc of about 0.85K in the AV_(3)Sb_(5) family(A=K,Rb,Cs)that severely challenges electronic spectroscopic probes.Here,utilizing dilution-refrigerator-based scanning tunneling microscopy down to 30 mK,we observe chiral 2×2 pair density waves with residual Fermi arcs in RbV_(3)Sb_(5).We find a superconducting gap of 150 μeV with substantial residual in-gap states.The spatial distribution of this gap exhibits chiral 2×2 modulations,signaling a chiral pair density wave(PDW).Our quasi-particle interference imaging of the zero-energy residual states further reveals arc-like patterns.We discuss the relation of the gap modulations with the residual Fermi arcs under the space-momentum correspondence between PDW and Bogoliubov Fermi states.展开更多
Flurbiprofen(FB),a nonsteroidal anti-inflammatory drug,is widely employed in treating ocular inflammation owing to its remarkable anti-inflammatory effects.However,the racemic nature of its commercially available form...Flurbiprofen(FB),a nonsteroidal anti-inflammatory drug,is widely employed in treating ocular inflammation owing to its remarkable anti-inflammatory effects.However,the racemic nature of its commercially available formulation(Ocufen^(R))limits the full potential of its therapeutic activity,as the(S)-enantiomer is responsible for the desired antiinflammatory effects.Additionally,the limited corneal permeability of FB significantly restricts its bioavailability.In this study,we successfully separated the chiral isomers of FB to obtain the highly active(S)-FB.Subsequently,utilizing ion-pairing technology,we coupled(S)-FB with various counter-ions,such as sodium,diethylamine,trimethamine(TMA),and l-arginine,to enhance its ocular bioavailability.A comprehensive evaluation encompassed balanced solubility,octanol-water partition coefficient,corneal permeability,ocular pharmacokinetics,tissue distribution,and in vivo ocular anti-inflammatory activity of each chiral isomer salt.Among the various formulations,S-FBTMA exhibited superior water solubility(about 1–12 mg/ml),lipid solubility(1<lgP_(ow)<3)and corneal permeability.In comparison to Ocufen^(R),S-FBTMA demonstrated significantly higher in vivo antiinflammatory activity and lower ocular irritability(such as conjunctival congestion and tingling).The findings from this research highlight the potential of chiral separation and ion-pair enhanced permeation techniques in providing pharmaceutical enterprises focused on drug development with a valuable avenue for improving therapeutic outcomes.展开更多
We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two ty...We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two typical bound states found above and below the energy bands,this system presents an extraordinary chiral bound state located within the energy gap.We use the chirality to quantify the breaking of the mirror symmetry.We find that the chirality value undergoes continuous changes by tuning the coupling strengths.The preferred direction of the chirality is controlled not only by the competition between the intracell and the intercell hoppings in the coupled-resonator array,but also by the coherence between the two coupling points.In the case with one coupling point,the chirality values varies monotonously with difference between the intracell hopping and the intercell hoppings.While in the case with two coupling points,due to the coherence between the two coupling points the perfect chiral states can be obtained.展开更多
Due to the lack of inversion,mirror or other roto-inversion symmetries,chiral crystals possess a well-defined handedness which,when combined with time-reversal symmetry breaking from the application of magnetic fields...Due to the lack of inversion,mirror or other roto-inversion symmetries,chiral crystals possess a well-defined handedness which,when combined with time-reversal symmetry breaking from the application of magnetic fields,can give rise to directional dichroism of the electrical transport phenomena via the magnetochiral anisotropy.In this study,we investigate the nonreciprocal magneto-transport in microdevices of NbGe_(2),a superconductor with structural chirality.A giant nonreciprocal signal from vortex motions is observed during the superconducting transition,with the ratio of nonreciprocal resistance to the normal resistanceγreaching 6×10^(5)T^(-1)·A^(-1).Interestingly,the intensity can be adjusted and even sign-reversed by varying the current,the temperature,and the crystalline orientation.Our findings illustrate intricate vortex dynamics and offer ways of manipulation on the rectification effect in superconductors with structural chirality.展开更多
Two-dimensional covalent organic frameworks(2D COFs)feature extendedπ-conjugation and ordered stacking sequence,showing great promise for high-performance photocatalysis.Periodic atomic frameworks of 2D COFs facilita...Two-dimensional covalent organic frameworks(2D COFs)feature extendedπ-conjugation and ordered stacking sequence,showing great promise for high-performance photocatalysis.Periodic atomic frameworks of 2D COFs facilitate the in-plane photogenerated charge transfer,but the precise ordered alignment is limited due to the non-covalentπ-stacking of COF layers,accordingly hindering out-of-plane transfer kinetics.Herein,we address a chiral induction method to construct a parallelly superimposed stacking chiral COF ultrathin shell on the support of SiO_(2) microsphere.Compared to the achiral COF analogues,the chiral COF shell with the parallel AA-stacking structure is more conducive to enhance the built-in electric field and accumulates photogenerated electrons for the rapid migration,thereby affording superior photocatalytic performance in hydrogen evolution from water splitting.Taking the simplest ketoenamine-linked chiral COF as a shell of SiO_(2) particle,the resulting composite exhibits an impressive hydrogen evolution rate of 107.1 mmol g^(-1)h^(-1)along with the apparent quantum efficiency of 14.31% at 475 nm.Furthermore,the composite photocatalysts could be fabricated into a film device,displaying a remarkable photocatalytic performance of 178.0 mmol m^(-2)h^(-1)for hydrogen evolution.Our work underpins the surface engineering of organic photocatalysts and illustrates the significance of COF stacking structures in regulating electronic properties.展开更多
In this paper,a multifunctional chiral metasurface is presented to achieve asymmetric transmission(AT)and linear-polarization conversion(LPC).The designed metasurface consists of a cross swords-like shape and two hole...In this paper,a multifunctional chiral metasurface is presented to achieve asymmetric transmission(AT)and linear-polarization conversion(LPC).The designed metasurface consists of a cross swords-like shape and two holes in the lower side of the unit cell.In the frequency band from 8.3 GHz to 10.4 GHz,AT is realized with more than 90%efficiency and the same chiral metasurface transforms linear polarized wave into its orthogonal counterpart with high efficiency.For LPC,the polarization conversion ratio(PCR)is greater than 95%.The proposed metasurface is stable against the incident angles of striking electromagnetic(EM)waves up to 60°for both operations of AT and LPC.展开更多
Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy absorption.This work extends the applications of chiral metam...Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy absorption.This work extends the applications of chiral metamaterials to underwater sound insulation.Various chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization scheme.Low acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL),while proper stiffness guarantees its robust acoustic performance under a hydrostatic pressure.As proof-of-concept demonstrations,two specimens are fabricated and tested in a water-filled impedance tube.Experimental results show that,on average,over 95%incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz,while the sound insulation performance keeps stable under a certain hydrostatic pressure.This work may provide new insights for chiral metamaterials into the underwater applications with sound insulation.展开更多
We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering pr...We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering problem by the variational method. We focus on a uniqueness result for the inverse scattering problem that is under what conditions an obstacle can be identified by the knowledge of the electric far-field pattern corresponding to all time-harmonic incident planes waves with a fixed wave number. To this end, we establish a chiral mixed reciprocity relation that connects the electric far-field pattern of a spherical wave with the scattered field of a plane wave.展开更多
We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion ...We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.展开更多
Aroma(volatile)compounds play important ecological functions in plants,and also contribute to the quality of plant-derived foods.Moreover,chiral aroma compounds affect their functions in plants and lead to different f...Aroma(volatile)compounds play important ecological functions in plants,and also contribute to the quality of plant-derived foods.Moreover,chiral aroma compounds affect their functions in plants and lead to different flavor quality properties.Formations of chiral aroma compounds are due to the presence of enzymes producing these compounds in plants,which are generally involved in the final biosynthetic step of the aroma compounds.Here,we review recent progress in research on the plant-derived enzymes producing chiral aroma compounds,and their changes in response to environmental factors.The chiral aroma enzymes that have been reported produce(R)-linalool,(S)-linalool,(R)-limonene,and(S)-limonene,etc.,and these enzymes are found in various plant species.We also discuss the origins of enantioselectivity in the plant-derived enzymes producing chiral aroma compounds and summarize the potential use of plants containing enzymes producing chiral aroma compounds for producing chiral flavors/fragrances.展开更多
For decades,chiral nanomaterials have been extensively studied because of their extraordinary properties.Chiral nanostructures have attracted a lot of interest because of their potential applications including biosens...For decades,chiral nanomaterials have been extensively studied because of their extraordinary properties.Chiral nanostructures have attracted a lot of interest because of their potential applications including biosensing,asymmetric catalysis,optical devices,and negative index materials.Circularly polarized light(CPL)is the most attractive source for chirality owing to its high availability,and now it has been used as a chiral source for the preparation of chiral matter.In this review,the recent progress in the field of CPL-enabled chiral nanomaterials is summarized.Firstly,the recent advancements in the fabrication of chiral materials using circularly polarized light are described,focusing on the unique strategies.Secondly,an overview of the potential applications of chiral nanomaterials driven by CPL is provided,with a particular emphasis on biosensing,catalysis,and phototherapy.Finally,a perspective on the challenges in the field of CPL-enabled chiral nanomaterials is given.展开更多
Chirality plays an important role in biological processes,and enantiomers often possess similar physical properties and different physiologic functions.In recent years,chiral detection of enantiomers become a popular ...Chirality plays an important role in biological processes,and enantiomers often possess similar physical properties and different physiologic functions.In recent years,chiral detection of enantiomers become a popular topic.Plasmonic metasurfaces enhance weak inherent chiral effects of biomolecules,so they are used in chiral detection.Artificial intelligence algorithm makes a lot of contribution to many aspects of nanophotonics.Here,we propose a nanostructure design method based on reinforcement learning and devise chiral nanostructures to distinguish enantiomers.The algorithm finds out the metallic nanostructures with a sharp peak in circular dichroism spectra and emphasizes the frequency shifts caused by nearfield interaction of nanostructures and biomolecules.Our work inspires universal and efficient machine-learning methods for nanophotonic design.展开更多
Capillary electrochromatography(CEC)plays a significant role in chiral separation via the double separation principle,partition coefficient difference between the two phases,and electroosmotic flow-driven separation.G...Capillary electrochromatography(CEC)plays a significant role in chiral separation via the double separation principle,partition coefficient difference between the two phases,and electroosmotic flow-driven separation.Given the distinct properties of the inner wall stationary phase(SP),the separation ability of each SP differs from one another.Particularly,it provides large room for promising applications of open tubular capillary electrochromatography(OT-CEC).We divided the OT-CEC SPs developed over the past four years into six types:ionic liquids,nanoparticle materials,microporous materials,biomaterials,non-nanopolymers,and others,to mainly introduce their characteristics in chiral drug separation.There also added a few classic SPs that occurred within ten years as supplements to enrich the features of each SP.Additionally,we discuss their applications in metabolomics,food,cosmetics,environment,and biology as analytes in addition to chiral drugs.OT-CEC plays an increasingly significant role in chiral separation and may promote the development of capillary electrophoresis(CE)combined with other instruments in recent years,such as CE with mass spectrometry(CE/MS)and CE with ultraviolet light detector(CE/UV).展开更多
Owing to the good adjustability and the strong near-field enhancement,surface plasmons are widely used in optical force trap,thus the optical force trap can achieve excellent performance.Here,we use the Laguerre–Gaus...Owing to the good adjustability and the strong near-field enhancement,surface plasmons are widely used in optical force trap,thus the optical force trap can achieve excellent performance.Here,we use the Laguerre–Gaussian beam and a plasmonic gold ring to separate enantiomers by the chiral optical force.Along with the radial optical force that traps the particles,there is also a chirality-sign-sensitive lateral force arising from the optical spin angular momentum,which is caused by the interaction between optical orbit angular momentum and gold ring structure.By selecting a specific incident wavelength,the strong angular scattering and non-chiral related azimuthal optical force can be suppressed.Thus the chiral related azimuthal optical force can induce an opposite orbital rotation of the trapped particles with chirality of different sign near the gold ring.This work proposes an effective approach for catchingand separating chiral enantiomers.展开更多
Chiral magnetic states are promising for future spintronic applications. Recent progress of chiral spin textures in two-dimensional magnets, such as chiral domain walls, skyrmions, and bimerons, have been drawing exte...Chiral magnetic states are promising for future spintronic applications. Recent progress of chiral spin textures in two-dimensional magnets, such as chiral domain walls, skyrmions, and bimerons, have been drawing extensive attention. Here, via first-principles calculations, we show that biaxial strain can effectively manipulate the magnetic parameters of the Janus Mn Se Te monolayer. Interestingly, we find that both the magnitude and the sign of the magnetic constants of the Heisenberg exchange coupling, Dzyaloshinskii–Moriya interaction and magnetocrystalline anisotropy can be tuned by strain. Moreover, using micromagnetic simulations, we obtain the distinct phase diagram of chiral spin texture under different strains. Especially, we demonstrate that abundant chiral magnetic structures including ferromagnetic skyrmion, skyrmionium, bimeron, and antiferromagnetic spin spiral can be induced in the Mn Se Te monolayer. We also discuss the effect of temperature on these magnetic structures. The findings highlight the Janus Mn Se Te monolayer as a good candidate for spintronic nanodevices.展开更多
We report the interplay between two different topological phases in condensed matter physics,the magnetic chiral domain wall(DW),and the quantum anomalous Hall(QAH)effect.It is shown that the chiral DW driven by Dzyal...We report the interplay between two different topological phases in condensed matter physics,the magnetic chiral domain wall(DW),and the quantum anomalous Hall(QAH)effect.It is shown that the chiral DW driven by Dzyaloshinskii–Moriya interaction can divide the uniform domain into several zones where the neighboring zone possesses opposite quantized Hall conductance.The separated domain with a chiral edge state(CES)can be continuously modified by external magnetic field-induced domain expansion and thermal fluctuation,which gives rise to the reconfigurable QAH effect.More interestingly,we show that the position of CES can be tuned by spin current driven chiral DW motion.Several two-dimensional magnets with high Curie temperature and large topological band gaps are proposed for realizing these phenomena.The present work thus reveals the possibility of chiral DW controllable QAH effects.展开更多
In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, it ...In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, it is predicted that in the nonrelativistic limit of certain collinear antiferromagnets, there exists a type of chiral“Dirac-like” fermion, whose dispersion manifests four-fold degenerate crossing points formed by spin-degenerate linear bands, with topologically protected Fermi arcs. Such an unconventional chiral fermion, protected by a hidden SU(2) symmetry in the hierarchy of an enhanced crystallographic group, namely spin space group, is not experimentally verified yet. Here, by angle-resolved photoemission spectroscopy measurements, we reveal the surface origin of the electron pocket at the Fermi surface in collinear antiferromagnet CoNb3S6. Combining with neutron diffraction and first-principles calculations, we suggest a multidomain collinear antiferromagnetic configuration, rendering the the existence of the Fermi-arc surface states induced by chiral Dirac-like fermions.Our work provides spectral evidence of the chiral Dirac-like fermion caused by particular spin symmetry in CoNb_(3)S_(6), paving an avenue for exploring new emergent phenomena in antiferromagnets with unconventional quasiparticle excitations.展开更多
Chiral metasurfaces have been proven to possess great potential in chiroptical applications.However,the multiband chiral metasurface with near-perfect circular dichroism has not been well studied.Also,the widely used ...Chiral metasurfaces have been proven to possess great potential in chiroptical applications.However,the multiband chiral metasurface with near-perfect circular dichroism has not been well studied.Also,the widely used bilayer metasurface usually suffers from the interlayer alignment and weak resonance.Here,we propose a twisted Moirémetasurface which can support three chiral bands with near-unity circular dichroism.The Moirémetasurface can remove the restriction of interlayer alignment,while maintaining a strong monolayer resonance.The two chiral bands in the forward direction can be described by two coupled-oscillator models.The third chiral band is achieved by tuning the interlayer chiral mode on resonance with the intralayer mode,to eliminate the parallel and converted components simultaneously.Finally,we study the robustness and tunability of the triple-layer Moirémetasurface in momentum space.This work provides a universal method to achieve three near-unity circular dichroism bands in one metasurface,which can promote applications of chiral metasurfaces in multiband optical communication,chiral drug separation,sensing,optical encryption,chiral laser,nonlinear and quantum optics,etc.展开更多
基金the support from the University of South Carolina
文摘Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate geometries.We designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed materials.We employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate conditions.These techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow relaxation.Furthermore,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting bath.These insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral domains.Our biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.
文摘Chirality(Greek“handiness”)is a property of many com-plex molecules.Chiral molecules exist in two forms,one being the mirror image of the other.Like for our hands,it is impossible to make the images identical by a suitable rota-tion.The two forms are called left-handed and right-handed.They have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a reflection.Other properties that are insensitive to the geometry are also the same.The different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same angle.However,the geometrical differences between the two species may have other conse-quences.The two species of the carvon molecule shown in Fig.1 taste quite differently.
基金supported by the National Key R&D Program of China(Grant Nos.2023YFA1407300,2023YFA1406500,2022YFA1403800,and 2023YFF0718403)the National Natural Science Foundation of China(Grant Nos.12374060,12274459,and 12074162)+2 种基金Guangdong Provincial Quantum Science Strategic Initiative(Grant No.GDZX2201001)the Beijing Natural Science Foundation(Grant No.Z200005)Guangdong Basic and Applied Basic Research Foundation(Grant No.2022B1515130005)。
文摘The chiral 2×2 charge order has been reported and confirmed in the kagome superconductor RbV_(3)Sb_(5),while its interplay with superconductivity remains elusive owing to its lowest superconducting transition temperature Tc of about 0.85K in the AV_(3)Sb_(5) family(A=K,Rb,Cs)that severely challenges electronic spectroscopic probes.Here,utilizing dilution-refrigerator-based scanning tunneling microscopy down to 30 mK,we observe chiral 2×2 pair density waves with residual Fermi arcs in RbV_(3)Sb_(5).We find a superconducting gap of 150 μeV with substantial residual in-gap states.The spatial distribution of this gap exhibits chiral 2×2 modulations,signaling a chiral pair density wave(PDW).Our quasi-particle interference imaging of the zero-energy residual states further reveals arc-like patterns.We discuss the relation of the gap modulations with the residual Fermi arcs under the space-momentum correspondence between PDW and Bogoliubov Fermi states.
基金financially supported by the National Postdoctoral Foundation of China(No.2023M730375)Liaoning Province Department of Education Project(No.LJKMZ20221365)the State Key Laboratory of Natural and Biomimetic Drugs(No.K202215)。
文摘Flurbiprofen(FB),a nonsteroidal anti-inflammatory drug,is widely employed in treating ocular inflammation owing to its remarkable anti-inflammatory effects.However,the racemic nature of its commercially available formulation(Ocufen^(R))limits the full potential of its therapeutic activity,as the(S)-enantiomer is responsible for the desired antiinflammatory effects.Additionally,the limited corneal permeability of FB significantly restricts its bioavailability.In this study,we successfully separated the chiral isomers of FB to obtain the highly active(S)-FB.Subsequently,utilizing ion-pairing technology,we coupled(S)-FB with various counter-ions,such as sodium,diethylamine,trimethamine(TMA),and l-arginine,to enhance its ocular bioavailability.A comprehensive evaluation encompassed balanced solubility,octanol-water partition coefficient,corneal permeability,ocular pharmacokinetics,tissue distribution,and in vivo ocular anti-inflammatory activity of each chiral isomer salt.Among the various formulations,S-FBTMA exhibited superior water solubility(about 1–12 mg/ml),lipid solubility(1<lgP_(ow)<3)and corneal permeability.In comparison to Ocufen^(R),S-FBTMA demonstrated significantly higher in vivo antiinflammatory activity and lower ocular irritability(such as conjunctival congestion and tingling).The findings from this research highlight the potential of chiral separation and ion-pair enhanced permeation techniques in providing pharmaceutical enterprises focused on drug development with a valuable avenue for improving therapeutic outcomes.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11975095,12075082,11935006,and 12247105)the Major Sci-Tech Program of Hunan Province,China(Grant No.2023ZJ1010)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2019A1515011400 and 2023A151501223).
文摘We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two typical bound states found above and below the energy bands,this system presents an extraordinary chiral bound state located within the energy gap.We use the chirality to quantify the breaking of the mirror symmetry.We find that the chirality value undergoes continuous changes by tuning the coupling strengths.The preferred direction of the chirality is controlled not only by the competition between the intracell and the intercell hoppings in the coupled-resonator array,but also by the coherence between the two coupling points.In the case with one coupling point,the chirality values varies monotonously with difference between the intracell hopping and the intercell hoppings.While in the case with two coupling points,due to the coherence between the two coupling points the perfect chiral states can be obtained.
基金Project supported by the National Key R&D Program of China(Grant No.2022YFA1403603)the National Natural Science Foundation of China(Grant Nos.U2032213,12104461,12374129,and 12304156)+1 种基金Chinese Academy of Sciences(Grant Nos.YSBR-084,and JZHKYPT-2021-08)A portion of this work was supported by the High Magnetic Field Laboratory of Anhui Province.
文摘Due to the lack of inversion,mirror or other roto-inversion symmetries,chiral crystals possess a well-defined handedness which,when combined with time-reversal symmetry breaking from the application of magnetic fields,can give rise to directional dichroism of the electrical transport phenomena via the magnetochiral anisotropy.In this study,we investigate the nonreciprocal magneto-transport in microdevices of NbGe_(2),a superconductor with structural chirality.A giant nonreciprocal signal from vortex motions is observed during the superconducting transition,with the ratio of nonreciprocal resistance to the normal resistanceγreaching 6×10^(5)T^(-1)·A^(-1).Interestingly,the intensity can be adjusted and even sign-reversed by varying the current,the temperature,and the crystalline orientation.Our findings illustrate intricate vortex dynamics and offer ways of manipulation on the rectification effect in superconductors with structural chirality.
文摘Two-dimensional covalent organic frameworks(2D COFs)feature extendedπ-conjugation and ordered stacking sequence,showing great promise for high-performance photocatalysis.Periodic atomic frameworks of 2D COFs facilitate the in-plane photogenerated charge transfer,but the precise ordered alignment is limited due to the non-covalentπ-stacking of COF layers,accordingly hindering out-of-plane transfer kinetics.Herein,we address a chiral induction method to construct a parallelly superimposed stacking chiral COF ultrathin shell on the support of SiO_(2) microsphere.Compared to the achiral COF analogues,the chiral COF shell with the parallel AA-stacking structure is more conducive to enhance the built-in electric field and accumulates photogenerated electrons for the rapid migration,thereby affording superior photocatalytic performance in hydrogen evolution from water splitting.Taking the simplest ketoenamine-linked chiral COF as a shell of SiO_(2) particle,the resulting composite exhibits an impressive hydrogen evolution rate of 107.1 mmol g^(-1)h^(-1)along with the apparent quantum efficiency of 14.31% at 475 nm.Furthermore,the composite photocatalysts could be fabricated into a film device,displaying a remarkable photocatalytic performance of 178.0 mmol m^(-2)h^(-1)for hydrogen evolution.Our work underpins the surface engineering of organic photocatalysts and illustrates the significance of COF stacking structures in regulating electronic properties.
文摘In this paper,a multifunctional chiral metasurface is presented to achieve asymmetric transmission(AT)and linear-polarization conversion(LPC).The designed metasurface consists of a cross swords-like shape and two holes in the lower side of the unit cell.In the frequency band from 8.3 GHz to 10.4 GHz,AT is realized with more than 90%efficiency and the same chiral metasurface transforms linear polarized wave into its orthogonal counterpart with high efficiency.For LPC,the polarization conversion ratio(PCR)is greater than 95%.The proposed metasurface is stable against the incident angles of striking electromagnetic(EM)waves up to 60°for both operations of AT and LPC.
基金supported by the National Natural Science Foundation of China(Nos.52171327,11991032,52201386,and 51805537)。
文摘Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy absorption.This work extends the applications of chiral metamaterials to underwater sound insulation.Various chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization scheme.Low acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL),while proper stiffness guarantees its robust acoustic performance under a hydrostatic pressure.As proof-of-concept demonstrations,two specimens are fabricated and tested in a water-filled impedance tube.Experimental results show that,on average,over 95%incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz,while the sound insulation performance keeps stable under a certain hydrostatic pressure.This work may provide new insights for chiral metamaterials into the underwater applications with sound insulation.
文摘We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering problem by the variational method. We focus on a uniqueness result for the inverse scattering problem that is under what conditions an obstacle can be identified by the knowledge of the electric far-field pattern corresponding to all time-harmonic incident planes waves with a fixed wave number. To this end, we establish a chiral mixed reciprocity relation that connects the electric far-field pattern of a spherical wave with the scattered field of a plane wave.
文摘We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential.
基金supported by the financial supports from the Guangdong Basic and Applied Basic Research Foundation(2020A1515010539)the Medical Science and Technology Research Foundation of Guangdong Province,China(A2019046)+1 种基金Guangdong Province Higher Vocational Colleges&Schools Pearl River Scholar(50117G25002)the Key Project of Universities in Guangdong Province(2021ZDZX4066).
文摘Aroma(volatile)compounds play important ecological functions in plants,and also contribute to the quality of plant-derived foods.Moreover,chiral aroma compounds affect their functions in plants and lead to different flavor quality properties.Formations of chiral aroma compounds are due to the presence of enzymes producing these compounds in plants,which are generally involved in the final biosynthetic step of the aroma compounds.Here,we review recent progress in research on the plant-derived enzymes producing chiral aroma compounds,and their changes in response to environmental factors.The chiral aroma enzymes that have been reported produce(R)-linalool,(S)-linalool,(R)-limonene,and(S)-limonene,etc.,and these enzymes are found in various plant species.We also discuss the origins of enantioselectivity in the plant-derived enzymes producing chiral aroma compounds and summarize the potential use of plants containing enzymes producing chiral aroma compounds for producing chiral flavors/fragrances.
基金financially the National Natural Science Foundation of China(51902136)the Fundamental Research Funds for the Central Universities(JUSRP12003,JUSRP622026)Natural Science Foundation of Jiangsu Province(BK20211236)。
文摘For decades,chiral nanomaterials have been extensively studied because of their extraordinary properties.Chiral nanostructures have attracted a lot of interest because of their potential applications including biosensing,asymmetric catalysis,optical devices,and negative index materials.Circularly polarized light(CPL)is the most attractive source for chirality owing to its high availability,and now it has been used as a chiral source for the preparation of chiral matter.In this review,the recent progress in the field of CPL-enabled chiral nanomaterials is summarized.Firstly,the recent advancements in the fabrication of chiral materials using circularly polarized light are described,focusing on the unique strategies.Secondly,an overview of the potential applications of chiral nanomaterials driven by CPL is provided,with a particular emphasis on biosensing,catalysis,and phototherapy.Finally,a perspective on the challenges in the field of CPL-enabled chiral nanomaterials is given.
基金This work is supported by the National Science Foundation of China(Grant Nos.12027807,62225501,and 11974002)National Key Research and Development Program of China(Grant No.2020YFA0211300,2020YFA0906900,and 2021YFF1200500)PKU-Baidu Fund Project(Grant No.2020BD023),and High-performance Computing Platform of Peking University.
文摘Chirality plays an important role in biological processes,and enantiomers often possess similar physical properties and different physiologic functions.In recent years,chiral detection of enantiomers become a popular topic.Plasmonic metasurfaces enhance weak inherent chiral effects of biomolecules,so they are used in chiral detection.Artificial intelligence algorithm makes a lot of contribution to many aspects of nanophotonics.Here,we propose a nanostructure design method based on reinforcement learning and devise chiral nanostructures to distinguish enantiomers.The algorithm finds out the metallic nanostructures with a sharp peak in circular dichroism spectra and emphasizes the frequency shifts caused by nearfield interaction of nanostructures and biomolecules.Our work inspires universal and efficient machine-learning methods for nanophotonic design.
基金This study was funded by the Project of National Natural Science Foundation of China(Grant No.:82003705)the Shanghai Science and Technology Innovation Foundation(Grant Nos.:23010500200 and 23ZR1422700).
文摘Capillary electrochromatography(CEC)plays a significant role in chiral separation via the double separation principle,partition coefficient difference between the two phases,and electroosmotic flow-driven separation.Given the distinct properties of the inner wall stationary phase(SP),the separation ability of each SP differs from one another.Particularly,it provides large room for promising applications of open tubular capillary electrochromatography(OT-CEC).We divided the OT-CEC SPs developed over the past four years into six types:ionic liquids,nanoparticle materials,microporous materials,biomaterials,non-nanopolymers,and others,to mainly introduce their characteristics in chiral drug separation.There also added a few classic SPs that occurred within ten years as supplements to enrich the features of each SP.Additionally,we discuss their applications in metabolomics,food,cosmetics,environment,and biology as analytes in addition to chiral drugs.OT-CEC plays an increasingly significant role in chiral separation and may promote the development of capillary electrophoresis(CE)combined with other instruments in recent years,such as CE with mass spectrometry(CE/MS)and CE with ultraviolet light detector(CE/UV).
基金Project supported by the National Natural Science Foundation of China (Grant No.12074054)the Fundamental Research Funds for the Central Universities,China (Grant No.DUT21LK06)。
文摘Owing to the good adjustability and the strong near-field enhancement,surface plasmons are widely used in optical force trap,thus the optical force trap can achieve excellent performance.Here,we use the Laguerre–Gaussian beam and a plasmonic gold ring to separate enantiomers by the chiral optical force.Along with the radial optical force that traps the particles,there is also a chirality-sign-sensitive lateral force arising from the optical spin angular momentum,which is caused by the interaction between optical orbit angular momentum and gold ring structure.By selecting a specific incident wavelength,the strong angular scattering and non-chiral related azimuthal optical force can be suppressed.Thus the chiral related azimuthal optical force can induce an opposite orbital rotation of the trapped particles with chirality of different sign near the gold ring.This work proposes an effective approach for catchingand separating chiral enantiomers.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1405102)the National Natural Science Foundation of China(Grant Nos.11874059 and 12174405)+4 种基金the Key Research Program of Frontier Sciences,CAS(Grant No.ZDBS-LY-7021)the Ningbo Key Scientific and Technological Project(Grant No.2021000215)the“Pioneer”and“Leading Goose”R&D Program of Zhejiang Province(Grant No.2022C01053)the Zhejiang Provincial Natural Science Foundation(Grant No.LR19A040002)Beijing National Laboratory for Condensed Matter Physics(Grant No.2021000123)。
文摘Chiral magnetic states are promising for future spintronic applications. Recent progress of chiral spin textures in two-dimensional magnets, such as chiral domain walls, skyrmions, and bimerons, have been drawing extensive attention. Here, via first-principles calculations, we show that biaxial strain can effectively manipulate the magnetic parameters of the Janus Mn Se Te monolayer. Interestingly, we find that both the magnitude and the sign of the magnetic constants of the Heisenberg exchange coupling, Dzyaloshinskii–Moriya interaction and magnetocrystalline anisotropy can be tuned by strain. Moreover, using micromagnetic simulations, we obtain the distinct phase diagram of chiral spin texture under different strains. Especially, we demonstrate that abundant chiral magnetic structures including ferromagnetic skyrmion, skyrmionium, bimeron, and antiferromagnetic spin spiral can be induced in the Mn Se Te monolayer. We also discuss the effect of temperature on these magnetic structures. The findings highlight the Janus Mn Se Te monolayer as a good candidate for spintronic nanodevices.
基金the National Natural Science Foundation of China(Grant Nos.11874059 and 12174405)the Key Research Program of Frontier Sciences,CAS(Grant No.ZDBS-LY-7021)+3 种基金the Ningbo Key Scientific and Technological Project(Grant No.2021000215)“Pioneer”and“Leading Goose”R&D Program of Zhejiang Province(Grant No.2022C01053)Zhejiang Provincial Natural Science Foundation(Grant No.LR19A040002)Beijing National Laboratory for Condensed Matter Physics(Grant No.2021000123)。
文摘We report the interplay between two different topological phases in condensed matter physics,the magnetic chiral domain wall(DW),and the quantum anomalous Hall(QAH)effect.It is shown that the chiral DW driven by Dzyaloshinskii–Moriya interaction can divide the uniform domain into several zones where the neighboring zone possesses opposite quantized Hall conductance.The separated domain with a chiral edge state(CES)can be continuously modified by external magnetic field-induced domain expansion and thermal fluctuation,which gives rise to the reconfigurable QAH effect.More interestingly,we show that the position of CES can be tuned by spin current driven chiral DW motion.Several two-dimensional magnets with high Curie temperature and large topological band gaps are proposed for realizing these phenomena.The present work thus reveals the possibility of chiral DW controllable QAH effects.
基金supported by the National Key R&D Program of China (Grant Nos. 2020YFA0308900 and 2022YFA1403700)the National Natural Science Foundation of China (Grant Nos. 12074163, 12134020, 11974157, 12104255, 12004159, and 12374146)+8 种基金Guangdong Provincial Key Laboratory for Computational Science and Material Design (Grant No. 2019B030301001)the Science, Technology and Innovation Commission of Shenzhen Municipality (Grant Nos. ZDSYS20190902092905285 and KQTD20190929173815000)Guangdong Basic and Applied Basic Research Foundation (Grant Nos. 2022B1515020046, 2021B1515130007, 2022A1515011915, 2019A1515110712, and 2022B1515130005)Shenzhen Science and Technology Program (Grant Nos. RCJC20221008092722009 and RCBS20210706092218039)the Guangdong Innovative and Entrepreneurial Research Team Program (Grant No. 2019ZT08C044)the beam time awarded by Australia’s Nuclear Science and Technology Organisation (ANSTO) (Grant No. P8130)the Materials and Life Science Experimental Facility of the Japan Proton Accelerator Research Complex (J-PARC) was performed under a user program (Proposal No. 2019B0140)performed at the Hiroshima Synchrotron Radiation Center (HiSOR) of Japan (Grant Nos. 22BG023 and 22BG029)Shanghai Synchrotron Radiation Facility (SSRF) BL03U (Grant No. 2022-SSRF-PT-020848)。
文摘In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, it is predicted that in the nonrelativistic limit of certain collinear antiferromagnets, there exists a type of chiral“Dirac-like” fermion, whose dispersion manifests four-fold degenerate crossing points formed by spin-degenerate linear bands, with topologically protected Fermi arcs. Such an unconventional chiral fermion, protected by a hidden SU(2) symmetry in the hierarchy of an enhanced crystallographic group, namely spin space group, is not experimentally verified yet. Here, by angle-resolved photoemission spectroscopy measurements, we reveal the surface origin of the electron pocket at the Fermi surface in collinear antiferromagnet CoNb3S6. Combining with neutron diffraction and first-principles calculations, we suggest a multidomain collinear antiferromagnetic configuration, rendering the the existence of the Fermi-arc surface states induced by chiral Dirac-like fermions.Our work provides spectral evidence of the chiral Dirac-like fermion caused by particular spin symmetry in CoNb_(3)S_(6), paving an avenue for exploring new emergent phenomena in antiferromagnets with unconventional quasiparticle excitations.
基金the National Natural Science Foundation of China(Grant Nos.12174031,91950108,and 11774035)。
文摘Chiral metasurfaces have been proven to possess great potential in chiroptical applications.However,the multiband chiral metasurface with near-perfect circular dichroism has not been well studied.Also,the widely used bilayer metasurface usually suffers from the interlayer alignment and weak resonance.Here,we propose a twisted Moirémetasurface which can support three chiral bands with near-unity circular dichroism.The Moirémetasurface can remove the restriction of interlayer alignment,while maintaining a strong monolayer resonance.The two chiral bands in the forward direction can be described by two coupled-oscillator models.The third chiral band is achieved by tuning the interlayer chiral mode on resonance with the intralayer mode,to eliminate the parallel and converted components simultaneously.Finally,we study the robustness and tunability of the triple-layer Moirémetasurface in momentum space.This work provides a universal method to achieve three near-unity circular dichroism bands in one metasurface,which can promote applications of chiral metasurfaces in multiband optical communication,chiral drug separation,sensing,optical encryption,chiral laser,nonlinear and quantum optics,etc.