This letter introduces the novel concept of Painlevé solitons—waves arising from the interaction between Painlevé waves and solitons in integrable systems.Painlevé solitons can also be viewed as solito...This letter introduces the novel concept of Painlevé solitons—waves arising from the interaction between Painlevé waves and solitons in integrable systems.Painlevé solitons can also be viewed as solitons propagating against a Painlevé wave background,in analogy to the established notion of elliptic solitons,which refers to solitons on an elliptic wave background.By employing a novel symmetry decomposition method aided by nonlocal residual symmetries,we explicitly construct (extended) Painlevé Ⅱ solitons for the Korteweg-de Vries equation and (extended) Painlevé Ⅳ solitons for the Boussinesq equation.展开更多
Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two ...Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two distinct scenarios: a non-symmetric Hamiltonian quench and a non-symmetric random quantum circuit, with a particular focus on U(1) symmetry. In the former case, symmetry remains broken in the subsystem at late times, whereas in the latter case, the symmetry is initially broken and subsequently restored, consistent with the principles of quantum thermalization. Notably, the growth of EA exhibits unexpected overshooting behavior at early times in both contexts, contrasting with the behavior of charge variance. We also consider dynamics of non-symmetric initial states under the symmetry-breaking evolution. Due to the competition of symmetry-breaking in both the initial state and Hamiltonian, the early-time EA can increase and decrease, while quantum Mpemba effects remain evident despite the weak symmetry-breaking in both settings.展开更多
Decays of charmonium into hyperon and antihyperon pairs provide a pristine laboratory for exploring hyperon properties,such as their polarization and decay parameters,and for conducting tests of fundamental symmetries...Decays of charmonium into hyperon and antihyperon pairs provide a pristine laboratory for exploring hyperon properties,such as their polarization and decay parameters,and for conducting tests of fundamental symmetries.This brief review highlights the significant progress made in precise tests of CP symmetry at BESIII using entangled hyperon-antihyperon pairs。展开更多
An improved method is proposed for the extraction of the symmetry energy coefficient relative to the temperature,a_(sym)/T,in the heavy-ion reactions near the Fermi energy region,based on the modified Fisher Model.Thi...An improved method is proposed for the extraction of the symmetry energy coefficient relative to the temperature,a_(sym)/T,in the heavy-ion reactions near the Fermi energy region,based on the modified Fisher Model.This method is applied to the primary fragments of antisymmetrized molecular dynamics(AMD)simulations for ^(46)Fe+^(46)Fe,^(40)Ca+^(40)Ca and ^(48)Ca+^(48)Ca at 35 MeV/nucleon,in order to make direct comparison to the results from the K(N,Z)method of Ono et al.In our improved method,the extracted values of a_(sym)/T increase as the size of isotopes increases whereas,in the K(N,Z)method,the results show rather constant behavior.This increase in our result is attributed to the surface contribution of the symmetry energy in finite nuclei.In order to evaluate the surface contribution,the relation a_(sym)/T=[a_(sym)^((V))(1-k_(S/V) A^(-1/3))]/T is applied and k_(S/V)=1.20~1.25 was extracted.This value is smaller than those extracted from the mass table,reflecting the weakened surface contribution at higher temperature regime.Δμ/T,the difference of the neutron-proton chemical potentials relative to the temperature,is also extracted in this method at the same time.The average values of the extractedΔμ/T,Δμ/T show a linear dependence on the proton-neutron a_(sym)metry parameter of the system,δ_(sys),andΔμ/T=(15.1±0.2)δ_(sys)-(0.5±0.1)is obtained.展开更多
Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this...Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this work, we systematically study the entanglement entropy(EE) and derivative entanglement entropy(DEE) near quantum phase transitions in various quantum many-body systems. A one-parameter scaling relation between the DEE and system size at the critical point has been derived for the first time, which successfully obtains the critical exponent via data collapse. Furthermore, we find that the EE peaks at the(emergent) symmetryenhanced first-order transition, reflecting higher symmetry breaking. This work provides a new paradigm for quantum many-body research from the perspective of EE and DEE.展开更多
The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoret...The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.展开更多
Achieving high-efficiency photoluminescence in trivalent lanthanides(Ln^(3+))requires precise crystalfield perturbation to overcome parity-forbidden 4f-transitions and suppress nonradiative decay.However,realizing suc...Achieving high-efficiency photoluminescence in trivalent lanthanides(Ln^(3+))requires precise crystalfield perturbation to overcome parity-forbidden 4f-transitions and suppress nonradiative decay.However,realizing such control remains challenging,even in well-optimized Ln^(3+) -doped nanocrystals.Here,by exploiting the atomically precise structure of metal nanoclusters,we demonstrate symmetry engineering in the Eu_(2)Ti_(4) nanoclusters through stepwise ligand substitution(BA/Phen→FBA/Phen→FBA/Bpy.BA:benzoicacid;Phen:1,10-phenanthroline;FBA:p-fluorobenzoicacid;Bpy:2,2'-bipyridine).The incorporation of FBA effectively suppresses nonradiative relaxation,while the flexible Bpy ligand induces symmetry reduction from D_(2d) to C_(2v) through coordination modulation,yielding a high photoluminescence quantum yield(PLQY)of 91.2%in the Ln^(3+) cluster systems.The transient-absorption,Judd-Ofelt theory,crystal-field analysis,and temperature-dependent photophysical studies elucidated the underlying modulation mechanisms.Furthermore,these clusters exhibit promising potential for optoelectronic applications,offering a new design strategy for high-performance luminescent materials.展开更多
Symmetry breaking,a critical phenomenon in both natural and artificial systems,is pivotal in constructing chiral structures from achiral building units.This study focuses on the achiral molecule 8,8',8'',8...Symmetry breaking,a critical phenomenon in both natural and artificial systems,is pivotal in constructing chiral structures from achiral building units.This study focuses on the achiral molecule 8,8',8'',8'''-((pyrazine-2,3,5,6-tetrayltetrakis(benzene-4,1-iyl))tetrakis(oxy))tetrakis(octan-1-ol)(TPP-C8OH),an aggregation-induced emission(AIE)molecule,to explore its symmetry breaking behavior in supramolecular assembly.By analyzing TPP-C8OH in various solvents—both non-chiral and chiral—we find that chiral solvents significantly enhance the molecule's symmetry breaking and chiroptical properties.Specially,alcohol solvents,particularly dodecyl alcohol,facilitate the formation of helical structures with both left-handed(M)and right-handed(P)helices within single twisted nanoribbons.This observation contrasts with previously reported symmetry breaking phenomena in assembly systems.Chiral solvents induce assemblies with distinct helical orientations,resulting in notable circularly polarized luminescence(CPL)and circular dichroism(CD)signals.This study elucidates the impact of solvent choice on symmetry breaking and chiral assembly,offering insights into the design of advanced chiral materials with tailored self-assembly processes.展开更多
Graph neural networks(GNNs)have demonstrated excellent performance in graph representation learning.However,as the volume of graph data grows,issues related to cost and efficiency become increasingly prominent.Graph d...Graph neural networks(GNNs)have demonstrated excellent performance in graph representation learning.However,as the volume of graph data grows,issues related to cost and efficiency become increasingly prominent.Graph distillation methods address this challenge by extracting a smaller,reduced graph,ensuring that GNNs trained on both the original and reduced graphs show similar performance.Existing methods,however,primarily optimize the feature matrix of the reduced graph and rely on correlation information from GNNs,while neglecting the original graph’s structure and redundant nodes.This often results in a loss of critical information within the reduced graph.To overcome this limitation,we propose a graph distillation method guided by network symmetry.Specifically,we identify symmetric nodes with equivalent neighborhood structures and merge them into“super nodes”,thereby simplifying the network structure,reducing redundant parameter optimization and enhancing training efficiency.At the same time,instead of relying on the original node features,we employ gradient descent to match optimal features that align with the original features,thus improving downstream task performance.Theoretically,our method guarantees that the reduced graph retains the key information present in the original graph.Extensive experiments demonstrate that our approach achieves significant improvements in graph distillation,exhibiting strong generalization capability and outperforming existing graph reduction methods.展开更多
Quantization noise caused by analog-to-digital converter(ADC)gives rise to the reliability performance degradation of communication systems.In this paper,a quantized non-Hermitian symmetry(NHS)orthogonal frequency-div...Quantization noise caused by analog-to-digital converter(ADC)gives rise to the reliability performance degradation of communication systems.In this paper,a quantized non-Hermitian symmetry(NHS)orthogonal frequency-division multiplexing-based visible light communication(OFDM-VLC)system is presented.In order to analyze the effect of the resolution of ADC on NHS OFDM-VLC,a quantized mathematical model of NHS OFDM-VLC is established.Based on the proposed quantized model,a closed-form bit error rate(BER)expression is derived.The theoretical analysis and simulation results both confirm the effectiveness of the obtained BER formula in high-resolution ADC.In addition,channel coding is helpful in compensating for the BER performance loss due to the utilization of lower resolution ADC.展开更多
The buckling-guided three-dimensional(3D)assembly method has arisen increasing attention for its advantages in forming complex 3D architectures with a rich diversity of geometric shapes in a broad spectrum of inorgani...The buckling-guided three-dimensional(3D)assembly method has arisen increasing attention for its advantages in forming complex 3D architectures with a rich diversity of geometric shapes in a broad spectrum of inorganic functional materials.Such an assembly method relies on the controlled lateral bucking of a 2D precursor structure integrated with a pre-stretched substrate at selective regions.In the assembly process,the preservation or break-ing of rotational symmetry is crucial for understanding the mechanism of 2D-to-3D geometric transformation.Here,we present a fundamental study on the rotational symmetry of 3D spoke double-ring structures formed through buckling-guided assembly.An energetic method is introduced to analyze the rotational symmetry and to understand the symmetry-breaking mechanism.Such symmetry-breaking phenomenon is validated by experi-ments and finite element analyses(FEA).Phase diagrams of the deformation mode are established to shed light on the influences of various geometric parameters(e.g.,initial rotational symmetry order,radius ratio,and lo-cation of bonding sites).This work offers new insights into the underlying mechanism of 2D-to-3D geometric transformation in ribbon-type structures formed by compressive buckling.展开更多
Altermagnetism,a recently identified class of collinear magnetism,combines key features of antiferromagnets and ferromagnets.Despite having zero net magnetization,altermagnetic materials exhibit anomalous transport ef...Altermagnetism,a recently identified class of collinear magnetism,combines key features of antiferromagnets and ferromagnets.Despite having zero net magnetization,altermagnetic materials exhibit anomalous transport effects,including the anomalous Hall,Nernst,and thermal Hall effects,as well as magneto-optical Kerr and Faraday effects.These phenomena,previously thought unique to ferromagnets,are dictated by symmetry,as confirmed by density functional theory(DFT)calculations.However,an effective model-based approach to verify these symmetry constraints remains unavailable.In this Letter,we construct a k·ρ model for d-wave altermagnets CuX_(2)(X=F,Cl)using spin space group representations and apply it to calculate the anomalous Hall effect.The symmetry-imposed transport properties predicted by the model are in agreement with the DFT results,providing a foundation for further investigation into symmetry-restricted transport phenomena in altermagnetic materials.展开更多
Phase engineering has proven to be an effective strategy for achieving superior thermoelectric performance,while pressure is an excellent means of expanding the phase space of a material.In this paper,the effect of pr...Phase engineering has proven to be an effective strategy for achieving superior thermoelectric performance,while pressure is an excellent means of expanding the phase space of a material.In this paper,the effect of pressure-induced phase transition on improving the crystal symmetry and enhancing the thermoelectric properties of AgCrSe2 under high pressure and high temperature are reported.A structural phase transition from the low-symmetry R3m phase to the high-symmetry P3m1 phase is discovered below 1 GPa,which increases band degeneracy and contributes to a high electrical conductivity.For the metallic P3m1 phase,the electrons surrounding the Se2−anion gradually transfer to the Ag+and Cr3+cations as the pressure increases,decreasing the density of states around the Fermi level and thus optimizing the carrier concentration,thereby increasing the Seebeck coefficient while maintaining a high electrical conductivity.Consequently,an ultrahigh power factor of 864μW⋅m−1⋅K−2 is achieved at 5 GPa and 297 K.This study provides new insights into improving thermoelectric transport properties by applying physical pressure to enhance crystal symmetry and optimize thermoelectric parameters,and also indicates that phase engineering is a compelling strategy to discover or design novel high-performance thermoelectric materials starting from low-symmetry compounds.展开更多
In this investigation,we delve into the interplay between strong interactions and intricate topological configurations,leading to emergent quantum states such as magnetic topological insulators.The crux of our researc...In this investigation,we delve into the interplay between strong interactions and intricate topological configurations,leading to emergent quantum states such as magnetic topological insulators.The crux of our research centers on elucidating how lattice symmetry modulates antiferromagnetic quantum Hall phenomena.Utilizing the spinful Harper-Hofstadter model enriched with a next-nearest-neighbor(NNN)hopping term,we discern a half-filling bandgap,paving the way for the manifestation of a quantum Hall insulator characterized by a Chern number,C=2.Upon integrating a checkerboardpatterned staggered potential(△)and the Hubbard interaction(U),the system exhibits complex dynamical behaviors.Marginal NNN hopping culminates in a Ne′el antiferromagnetic Mott insulator.In contrast,intensified hopping results in stripe antiferromagnetic configurations.Moreover,in the regime of limited NNN hopping,a C=1 Ne′el antiferromagnetic quantum Hall insulator emerges.A salient observation pertains to the manifestation of a C=1 antiferromagnetic quantum Hall insulator when spin-flip mechanisms are not offset by space group symmetries.These findings chart a pathway for further explorations into antiferromagnetic Quantum Hall States.展开更多
We have performed a comparative study of the photoelectron spectra adopting different initial states(2s or 2_(p0))of hydrogen atoms in a near-infrared laser pulse by using the full three-dimensional time-dependent Sch...We have performed a comparative study of the photoelectron spectra adopting different initial states(2s or 2_(p0))of hydrogen atoms in a near-infrared laser pulse by using the full three-dimensional time-dependent Schr?dinger equation.It is demonstrated that the atomic photoelectron spectra oscillate out of step as a function of electron kinetic energies for different initial states(2s or 2_(p0)),which is well reproduced by the simulations based on strong field approximation,and the above distinct feature is ascribed to the different interferences from the partial electron wave packets detached by positive and negative electric fields for different initial states of 2s and 2_(p0).展开更多
In this paper,the Drinfeld-Sokolov-Satsuma-Hirota(DSSH)system is studied by using residual symmetry and the consistent Riccati expansion(CRE)method,respectively.The residual symmetry of the DSSH system is localized to...In this paper,the Drinfeld-Sokolov-Satsuma-Hirota(DSSH)system is studied by using residual symmetry and the consistent Riccati expansion(CRE)method,respectively.The residual symmetry of the DSSH system is localized to Lie point symmetry in a properly prolonged system,based on which we get a new Bäcklund transformation for this system.New symmetry reduction solutions of the DSSH system are obtained by applying the classical Lie group approach on the prolonged system.Moreover,the DSSH system proves to be CRE integrable and new interesting interaction solutions between solitons and periodic waves are generated and analyzed.展开更多
We theoretically investigate a one-dimensional Su–Schrieffer–Heeger(SSH)model with spin–orbit coupling(SOC)and sublattice-dependent gain and loss.As the gain and loss increase,the system transitions from a parity-t...We theoretically investigate a one-dimensional Su–Schrieffer–Heeger(SSH)model with spin–orbit coupling(SOC)and sublattice-dependent gain and loss.As the gain and loss increase,the system transitions from a parity-time(PT)symmetric phase to a parity-time and anti-parity-time(PT&APT)symmetry-breaking phase,and finally to an anti-paritytime(APT)symmetric phase.Notably,when the intracell and intercell hopping,intracell and intercell SOC parameters are all equal to half the gain–loss parameter,the model exhibits a doubly degenerate exceptional point(EP).When the SOC is equal for intracell and intercell interactions,a stronger hopping mechanism within cells compared to that between cells results in an increase in SOC that transitions the Zak phase from zero to a non-quantized value,eventually arriving at one.In contrast,a reduction in the strength of intracell hopping leads the Zak phase to transition from two to a non-quantized value,eventually arriving at one.If the intracell and intercell SOC are not aligned,altering these couplings leads to a shift in the Zak phase from two to a non-quantized level,then to one,re-entering the non-quantized region,and eventually arriving at zero.We suggest a practical experimental setup for our model that can be implemented using electrical circuits.展开更多
In this note we describe a logarithmic version of mirror Landau-Ginzburg model for semi-projective toric manifolds and show in an elementary and explicit way that the state space ring of the Landau-Ginzburg mirror is ...In this note we describe a logarithmic version of mirror Landau-Ginzburg model for semi-projective toric manifolds and show in an elementary and explicit way that the state space ring of the Landau-Ginzburg mirror is isomorphic to the C-valued cohomology of the toric manifold.展开更多
The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW...The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW).Most recently,a chiral CDW has been suggested in kagome magnet FeGe,but the related study is very rare.Here,we use a scanning tunneling microscope to study the symmetry breaking behavior of both the short-and long-range CDWs in FeGe.Different from previous studies,our study reveals an isotropic long-range CDW without obvious symmetry breaking,while local rotational symmetry breaking appears in the short-range CDW,which may be related to the existence of strong structural disorders.Moreover,the charge distribution of the short-range CDW is inert to the applied external magnetic fields and the detailed spin arrangements of FeGe,inconsistent with the expectation of a chiral CDW associated with chiral flux.Our results rule out the existence of spontaneous chiral and rotational symmetry breaking in the CDW state of FeGe,putting strong constraints on the further understanding of CDW mechanism.展开更多
In this paper,we constrain the symmetry energy at high densities in nuclear matter using recent observations of neutron stars based on the calculations of relativistic mean-field models.Using the observations of the n...In this paper,we constrain the symmetry energy at high densities in nuclear matter using recent observations of neutron stars based on the calculations of relativistic mean-field models.Using the observations of the neutron stars,we obtain the constraint on the symmetry energy at high densities,S(2_(ρ_(0)))=40.54±12.47 MeV,and S(3_(ρ_(0)))=44.12±29.38 MeV.展开更多
基金supported by the National Natural Science Foundations of China (Grant Nos.12235007,12001424,12271324,and 12501333)the Natural Science Basic research program of Shaanxi Province (Grant Nos.2021JZ-21 and 2024JC-YBQN-0069)+3 种基金the China Postdoctoral Science Foundation (Grant Nos.2020M673332 and 2024M751921)the Fundamental Research Funds for the Central Universities (Grant No.GK202304028)the 2023 Shaanxi Province Postdoctoral Research Project (Grant No.2023BSHEDZZ186)Xi’an University,Xi’an Science and Technology Plan Wutongshu Technology Transfer Action Innovation Team(Grant No.25WTZD07)。
文摘This letter introduces the novel concept of Painlevé solitons—waves arising from the interaction between Painlevé waves and solitons in integrable systems.Painlevé solitons can also be viewed as solitons propagating against a Painlevé wave background,in analogy to the established notion of elliptic solitons,which refers to solitons on an elliptic wave background.By employing a novel symmetry decomposition method aided by nonlocal residual symmetries,we explicitly construct (extended) Painlevé Ⅱ solitons for the Korteweg-de Vries equation and (extended) Painlevé Ⅳ solitons for the Boussinesq equation.
基金the support of the International Young Scientist Fellowship of the Institute of Physics,Chinese Academy of Sciences (Grant No.202407)supported by the Innovation Program for Quantum Science and Technology (Grant No.2024ZD0301700)+1 种基金the start-up grant at IOP-CAS.ZXL is supported by the Beijing Natural Science Foundation (Grant No.JR25007)the National Natural Science Foundation of China (Grants No.12347107and 12474146)。
文摘Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two distinct scenarios: a non-symmetric Hamiltonian quench and a non-symmetric random quantum circuit, with a particular focus on U(1) symmetry. In the former case, symmetry remains broken in the subsystem at late times, whereas in the latter case, the symmetry is initially broken and subsequently restored, consistent with the principles of quantum thermalization. Notably, the growth of EA exhibits unexpected overshooting behavior at early times in both contexts, contrasting with the behavior of charge variance. We also consider dynamics of non-symmetric initial states under the symmetry-breaking evolution. Due to the competition of symmetry-breaking in both the initial state and Hamiltonian, the early-time EA can increase and decrease, while quantum Mpemba effects remain evident despite the weak symmetry-breaking in both settings.
基金supported by the National Natural Science Foundation of China(Grant No.12225509),the National Natural Science Foundation of China(Grant No.12247101)the Polish National Science Centre(Grant No.2024/53/B/ST2/00975)+2 种基金the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2024-jdzx06)the Natural Science Foundation of Gansu Province(Grant No.22JR5RA389)the‘111 Center’under Grant No.B20063。
文摘Decays of charmonium into hyperon and antihyperon pairs provide a pristine laboratory for exploring hyperon properties,such as their polarization and decay parameters,and for conducting tests of fundamental symmetries.This brief review highlights the significant progress made in precise tests of CP symmetry at BESIII using entangled hyperon-antihyperon pairs。
文摘An improved method is proposed for the extraction of the symmetry energy coefficient relative to the temperature,a_(sym)/T,in the heavy-ion reactions near the Fermi energy region,based on the modified Fisher Model.This method is applied to the primary fragments of antisymmetrized molecular dynamics(AMD)simulations for ^(46)Fe+^(46)Fe,^(40)Ca+^(40)Ca and ^(48)Ca+^(48)Ca at 35 MeV/nucleon,in order to make direct comparison to the results from the K(N,Z)method of Ono et al.In our improved method,the extracted values of a_(sym)/T increase as the size of isotopes increases whereas,in the K(N,Z)method,the results show rather constant behavior.This increase in our result is attributed to the surface contribution of the symmetry energy in finite nuclei.In order to evaluate the surface contribution,the relation a_(sym)/T=[a_(sym)^((V))(1-k_(S/V) A^(-1/3))]/T is applied and k_(S/V)=1.20~1.25 was extracted.This value is smaller than those extracted from the mass table,reflecting the weakened surface contribution at higher temperature regime.Δμ/T,the difference of the neutron-proton chemical potentials relative to the temperature,is also extracted in this method at the same time.The average values of the extractedΔμ/T,Δμ/T show a linear dependence on the proton-neutron a_(sym)metry parameter of the system,δ_(sys),andΔμ/T=(15.1±0.2)δ_(sys)-(0.5±0.1)is obtained.
基金supported by the the National Natural Science Foundation of China(Grant Nos.12175015 for W.G.and 12174387 for L.Z.)the Chinese Academy of Sciences (Grant Nos.YSBR-057 and JZHKYPT-2021-08 for L.Z.)+1 种基金the Innovative Program for Quantum Science and Technology (Grant No.2021ZD0302600 for L.Z.)the start-up funding of Westlake University and the China Postdoctoral Science Foundation (Grant No.2024M752898 for Z.W.and Z.Y.)。
文摘Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this work, we systematically study the entanglement entropy(EE) and derivative entanglement entropy(DEE) near quantum phase transitions in various quantum many-body systems. A one-parameter scaling relation between the DEE and system size at the critical point has been derived for the first time, which successfully obtains the critical exponent via data collapse. Furthermore, we find that the EE peaks at the(emergent) symmetryenhanced first-order transition, reflecting higher symmetry breaking. This work provides a new paradigm for quantum many-body research from the perspective of EE and DEE.
基金the full support of the National Natural Science Foundation of China(62071154,51272052 and50902040)the Natural Science Foundation of Heilongjiang Province of China(LH2020B011 and LH2019B006)the Scientific Research Projects of Basic Scientific Research Operational Expenses of Heilongjiang Provincial Colleges and Universities(2021-KYYWF-0171)。
文摘The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.
基金Project supported by the National Key Research and Development Program of China(2024YFE0206100)the National Natural Science Foundation of China(T2325015,U21A2068,12174151)。
文摘Achieving high-efficiency photoluminescence in trivalent lanthanides(Ln^(3+))requires precise crystalfield perturbation to overcome parity-forbidden 4f-transitions and suppress nonradiative decay.However,realizing such control remains challenging,even in well-optimized Ln^(3+) -doped nanocrystals.Here,by exploiting the atomically precise structure of metal nanoclusters,we demonstrate symmetry engineering in the Eu_(2)Ti_(4) nanoclusters through stepwise ligand substitution(BA/Phen→FBA/Phen→FBA/Bpy.BA:benzoicacid;Phen:1,10-phenanthroline;FBA:p-fluorobenzoicacid;Bpy:2,2'-bipyridine).The incorporation of FBA effectively suppresses nonradiative relaxation,while the flexible Bpy ligand induces symmetry reduction from D_(2d) to C_(2v) through coordination modulation,yielding a high photoluminescence quantum yield(PLQY)of 91.2%in the Ln^(3+) cluster systems.The transient-absorption,Judd-Ofelt theory,crystal-field analysis,and temperature-dependent photophysical studies elucidated the underlying modulation mechanisms.Furthermore,these clusters exhibit promising potential for optoelectronic applications,offering a new design strategy for high-performance luminescent materials.
基金support from the National Natural Science Foundation of China(Nos.22471198,22101208)the Fundamental Research Funds for the Central Universities.
文摘Symmetry breaking,a critical phenomenon in both natural and artificial systems,is pivotal in constructing chiral structures from achiral building units.This study focuses on the achiral molecule 8,8',8'',8'''-((pyrazine-2,3,5,6-tetrayltetrakis(benzene-4,1-iyl))tetrakis(oxy))tetrakis(octan-1-ol)(TPP-C8OH),an aggregation-induced emission(AIE)molecule,to explore its symmetry breaking behavior in supramolecular assembly.By analyzing TPP-C8OH in various solvents—both non-chiral and chiral—we find that chiral solvents significantly enhance the molecule's symmetry breaking and chiroptical properties.Specially,alcohol solvents,particularly dodecyl alcohol,facilitate the formation of helical structures with both left-handed(M)and right-handed(P)helices within single twisted nanoribbons.This observation contrasts with previously reported symmetry breaking phenomena in assembly systems.Chiral solvents induce assemblies with distinct helical orientations,resulting in notable circularly polarized luminescence(CPL)and circular dichroism(CD)signals.This study elucidates the impact of solvent choice on symmetry breaking and chiral assembly,offering insights into the design of advanced chiral materials with tailored self-assembly processes.
基金Project supported by the National Natural Science Foundation of China(Grant No.62176217)the Program from the Sichuan Provincial Science and Technology,China(Grant No.2018RZ0081)the Fundamental Research Funds of China West Normal University(Grant No.17E063).
文摘Graph neural networks(GNNs)have demonstrated excellent performance in graph representation learning.However,as the volume of graph data grows,issues related to cost and efficiency become increasingly prominent.Graph distillation methods address this challenge by extracting a smaller,reduced graph,ensuring that GNNs trained on both the original and reduced graphs show similar performance.Existing methods,however,primarily optimize the feature matrix of the reduced graph and rely on correlation information from GNNs,while neglecting the original graph’s structure and redundant nodes.This often results in a loss of critical information within the reduced graph.To overcome this limitation,we propose a graph distillation method guided by network symmetry.Specifically,we identify symmetric nodes with equivalent neighborhood structures and merge them into“super nodes”,thereby simplifying the network structure,reducing redundant parameter optimization and enhancing training efficiency.At the same time,instead of relying on the original node features,we employ gradient descent to match optimal features that align with the original features,thus improving downstream task performance.Theoretically,our method guarantees that the reduced graph retains the key information present in the original graph.Extensive experiments demonstrate that our approach achieves significant improvements in graph distillation,exhibiting strong generalization capability and outperforming existing graph reduction methods.
基金supported by the National Natural Science Foundation of China(No.62201508)the Zhejiang Provincial Natural Science Foundation of China(Nos.LZ21F010001 and LQ23F010004)the State Key Laboratory of Millimeter Waves of Southeast University,China(No.K202212).
文摘Quantization noise caused by analog-to-digital converter(ADC)gives rise to the reliability performance degradation of communication systems.In this paper,a quantized non-Hermitian symmetry(NHS)orthogonal frequency-division multiplexing-based visible light communication(OFDM-VLC)system is presented.In order to analyze the effect of the resolution of ADC on NHS OFDM-VLC,a quantized mathematical model of NHS OFDM-VLC is established.Based on the proposed quantized model,a closed-form bit error rate(BER)expression is derived.The theoretical analysis and simulation results both confirm the effectiveness of the obtained BER formula in high-resolution ADC.In addition,channel coding is helpful in compensating for the BER performance loss due to the utilization of lower resolution ADC.
基金supported by the National Natural Science Foundation of China(Grant Nos.12225206,11921002,and 12202233)the New Cornerstone Science Foundation through the XPLORER PRIZE,the Tsinghua National Laboratory for Information Science and Technology,a grant from the Institute for Guo Qiang,Tsinghua University(Grant No.2021GQG1009)。
文摘The buckling-guided three-dimensional(3D)assembly method has arisen increasing attention for its advantages in forming complex 3D architectures with a rich diversity of geometric shapes in a broad spectrum of inorganic functional materials.Such an assembly method relies on the controlled lateral bucking of a 2D precursor structure integrated with a pre-stretched substrate at selective regions.In the assembly process,the preservation or break-ing of rotational symmetry is crucial for understanding the mechanism of 2D-to-3D geometric transformation.Here,we present a fundamental study on the rotational symmetry of 3D spoke double-ring structures formed through buckling-guided assembly.An energetic method is introduced to analyze the rotational symmetry and to understand the symmetry-breaking mechanism.Such symmetry-breaking phenomenon is validated by experi-ments and finite element analyses(FEA).Phase diagrams of the deformation mode are established to shed light on the influences of various geometric parameters(e.g.,initial rotational symmetry order,radius ratio,and lo-cation of bonding sites).This work offers new insights into the underlying mechanism of 2D-to-3D geometric transformation in ribbon-type structures formed by compressive buckling.
基金supported by the National Natural Science Foundation of China(Grant No.12274117)the Natural Science Foundation of Henan(Grant No.242300421214)+4 种基金the Program for Innovative Research Team(in Science and Technology)in the University of Henan Province(Grant No.24IRTSTHN025)the Open Fund of Guangdong Provincial Key Laboratory of Nanophotonic Manipulation(No.202502)Guangdong S&T Program(No.2023B1212010008)the High-Performance Computing Center of Henan Normal Universitysupported by the U.S.DOE,Office of Science(Grant No.DE-FG02-05ER46237)。
文摘Altermagnetism,a recently identified class of collinear magnetism,combines key features of antiferromagnets and ferromagnets.Despite having zero net magnetization,altermagnetic materials exhibit anomalous transport effects,including the anomalous Hall,Nernst,and thermal Hall effects,as well as magneto-optical Kerr and Faraday effects.These phenomena,previously thought unique to ferromagnets,are dictated by symmetry,as confirmed by density functional theory(DFT)calculations.However,an effective model-based approach to verify these symmetry constraints remains unavailable.In this Letter,we construct a k·ρ model for d-wave altermagnets CuX_(2)(X=F,Cl)using spin space group representations and apply it to calculate the anomalous Hall effect.The symmetry-imposed transport properties predicted by the model are in agreement with the DFT results,providing a foundation for further investigation into symmetry-restricted transport phenomena in altermagnetic materials.
基金supported by the Jilin Province Science and Technology Development Program,China(Grant No.20250102013JC).
文摘Phase engineering has proven to be an effective strategy for achieving superior thermoelectric performance,while pressure is an excellent means of expanding the phase space of a material.In this paper,the effect of pressure-induced phase transition on improving the crystal symmetry and enhancing the thermoelectric properties of AgCrSe2 under high pressure and high temperature are reported.A structural phase transition from the low-symmetry R3m phase to the high-symmetry P3m1 phase is discovered below 1 GPa,which increases band degeneracy and contributes to a high electrical conductivity.For the metallic P3m1 phase,the electrons surrounding the Se2−anion gradually transfer to the Ag+and Cr3+cations as the pressure increases,decreasing the density of states around the Fermi level and thus optimizing the carrier concentration,thereby increasing the Seebeck coefficient while maintaining a high electrical conductivity.Consequently,an ultrahigh power factor of 864μW⋅m−1⋅K−2 is achieved at 5 GPa and 297 K.This study provides new insights into improving thermoelectric transport properties by applying physical pressure to enhance crystal symmetry and optimize thermoelectric parameters,and also indicates that phase engineering is a compelling strategy to discover or design novel high-performance thermoelectric materials starting from low-symmetry compounds.
文摘In this investigation,we delve into the interplay between strong interactions and intricate topological configurations,leading to emergent quantum states such as magnetic topological insulators.The crux of our research centers on elucidating how lattice symmetry modulates antiferromagnetic quantum Hall phenomena.Utilizing the spinful Harper-Hofstadter model enriched with a next-nearest-neighbor(NNN)hopping term,we discern a half-filling bandgap,paving the way for the manifestation of a quantum Hall insulator characterized by a Chern number,C=2.Upon integrating a checkerboardpatterned staggered potential(△)and the Hubbard interaction(U),the system exhibits complex dynamical behaviors.Marginal NNN hopping culminates in a Ne′el antiferromagnetic Mott insulator.In contrast,intensified hopping results in stripe antiferromagnetic configurations.Moreover,in the regime of limited NNN hopping,a C=1 Ne′el antiferromagnetic quantum Hall insulator emerges.A salient observation pertains to the manifestation of a C=1 antiferromagnetic quantum Hall insulator when spin-flip mechanisms are not offset by space group symmetries.These findings chart a pathway for further explorations into antiferromagnetic Quantum Hall States.
基金Project supported by Li Ka Shing Foundation STUGTIIT Joint Research(Grant No.2024LKSFG02)the STU Scientific Research Foundation for Talents(Grant Nos.NTF22026,NTF23011,NTF23014,and NTF23036T)+1 种基金the National Basic Research Program of China(Grant No.2019YFA0307700)the National Natural Science Foundation of China(Grant Nos.12074239 and 12274300)。
文摘We have performed a comparative study of the photoelectron spectra adopting different initial states(2s or 2_(p0))of hydrogen atoms in a near-infrared laser pulse by using the full three-dimensional time-dependent Schr?dinger equation.It is demonstrated that the atomic photoelectron spectra oscillate out of step as a function of electron kinetic energies for different initial states(2s or 2_(p0)),which is well reproduced by the simulations based on strong field approximation,and the above distinct feature is ascribed to the different interferences from the partial electron wave packets detached by positive and negative electric fields for different initial states of 2s and 2_(p0).
基金supported by the National Natural Science Foundation of China under Grant Nos.12175148 and 11975156。
文摘In this paper,the Drinfeld-Sokolov-Satsuma-Hirota(DSSH)system is studied by using residual symmetry and the consistent Riccati expansion(CRE)method,respectively.The residual symmetry of the DSSH system is localized to Lie point symmetry in a properly prolonged system,based on which we get a new Bäcklund transformation for this system.New symmetry reduction solutions of the DSSH system are obtained by applying the classical Lie group approach on the prolonged system.Moreover,the DSSH system proves to be CRE integrable and new interesting interaction solutions between solitons and periodic waves are generated and analyzed.
基金Project supported by the Natural Science Foundation of Chongqing,China(Grant No.CSTB2024NSCQ-MSX0736)Science and Technology Innovation Key R&D Program of Chongqing(Grant No.CSTB2024TIAD-STX0035)the Research Foundation of Institute for Advanced Sciences of CQUPT(Grant No.E011A2022328)。
文摘We theoretically investigate a one-dimensional Su–Schrieffer–Heeger(SSH)model with spin–orbit coupling(SOC)and sublattice-dependent gain and loss.As the gain and loss increase,the system transitions from a parity-time(PT)symmetric phase to a parity-time and anti-parity-time(PT&APT)symmetry-breaking phase,and finally to an anti-paritytime(APT)symmetric phase.Notably,when the intracell and intercell hopping,intracell and intercell SOC parameters are all equal to half the gain–loss parameter,the model exhibits a doubly degenerate exceptional point(EP).When the SOC is equal for intracell and intercell interactions,a stronger hopping mechanism within cells compared to that between cells results in an increase in SOC that transitions the Zak phase from zero to a non-quantized value,eventually arriving at one.In contrast,a reduction in the strength of intracell hopping leads the Zak phase to transition from two to a non-quantized value,eventually arriving at one.If the intracell and intercell SOC are not aligned,altering these couplings leads to a shift in the Zak phase from two to a non-quantized level,then to one,re-entering the non-quantized region,and eventually arriving at zero.We suggest a practical experimental setup for our model that can be implemented using electrical circuits.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.12201314).
文摘In this note we describe a logarithmic version of mirror Landau-Ginzburg model for semi-projective toric manifolds and show in an elementary and explicit way that the state space ring of the Landau-Ginzburg mirror is isomorphic to the C-valued cohomology of the toric manifold.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12374140,12494593,11790312,12004056,11774060,and 92065201)the National Key R&D Program of China(Grant No.2023YFA1406304)+2 种基金the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302803)the Fundamental Research Funds for the Central Universities of China(Grant Nos.2022CDJXY-002 and WK9990000103)the New Cornerstone Science Foundation.
文摘The complex symmetry breaking states in AV3Sb5 family have attracted extreme research attention,but controversy still exists,especially in the question of time reversal symmetry breaking of the charge density wave(CDW).Most recently,a chiral CDW has been suggested in kagome magnet FeGe,but the related study is very rare.Here,we use a scanning tunneling microscope to study the symmetry breaking behavior of both the short-and long-range CDWs in FeGe.Different from previous studies,our study reveals an isotropic long-range CDW without obvious symmetry breaking,while local rotational symmetry breaking appears in the short-range CDW,which may be related to the existence of strong structural disorders.Moreover,the charge distribution of the short-range CDW is inert to the applied external magnetic fields and the detailed spin arrangements of FeGe,inconsistent with the expectation of a chiral CDW associated with chiral flux.Our results rule out the existence of spontaneous chiral and rotational symmetry breaking in the CDW state of FeGe,putting strong constraints on the further understanding of CDW mechanism.
基金supported by the National Natural Science Foundation of China(Nos.12275359,12375129,11875323,and 11961141003)the National Key R&D Program of China(No.2023YFA1606402)+2 种基金the Continuous Basic Scientific Research Project,the China Institute of Atomic Energy(Nos.YZ222407001301 and YZ232604001601)the Leading Innovation Project of the CNNC(Nos.LC192209000701 and LC202309000201)the computing server SCATP in China Institute of Atomic Energy and Basic Research Special Zone.
文摘In this paper,we constrain the symmetry energy at high densities in nuclear matter using recent observations of neutron stars based on the calculations of relativistic mean-field models.Using the observations of the neutron stars,we obtain the constraint on the symmetry energy at high densities,S(2_(ρ_(0)))=40.54±12.47 MeV,and S(3_(ρ_(0)))=44.12±29.38 MeV.