The 19th century saw significant advancements in thermodynamics and the kinetic theory of gases,with J.C.Maxwell and L.E.Boltzmann playing key roles in the development of statistical physics through their work on the ...The 19th century saw significant advancements in thermodynamics and the kinetic theory of gases,with J.C.Maxwell and L.E.Boltzmann playing key roles in the development of statistical physics through their work on the distribution of single-particle states.At the beginning of the 20th century,J.W.Gibbs established modern equilibrium statistical physics based on the statistical distribution of system microstates and the concept of ensembles.Subsequently,statistical physics expanded into the quantum and nonequilibrium domains.展开更多
As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclea...As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclear cluster physics.In this review,we briefly revisit the theoretical framework for calculating the reduced-width amplitude,as well as the outlines of cluster models to obtain microscopic or semi-microscopic cluster wave functions.We also introduce the recent progress related to cluster overlap amplitudes,including the implementation of cross-section estimation and extension to three-body clustering analysis.Comprehensive examples are provided to demonstrate the application of the reduced-width amplitude in analyzing clustering structures.展开更多
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF...The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result.展开更多
It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range ...It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range of crystallographic directions of shock loading has not been revealed.In this work,we calculated the shock Hugoniot for aluminum and copper in different crystallographic directions([100],[110],[111],[112],[102],[114],[123],[134],[221]and[401])of shock compression using molecular dynamics(MD)simulations.The results showed a high pressure(>160 GPa for Cu and>40 GPa for Al)of the FCC-to-BCC transition.In copper,different characteristics of the phase transition are observed depending on the loading direction with the[100]compression direction being the weakest.The FCC-to-BCC transition for copper is in the range of 150–220 GPa,which is consistent with the existing experimental data.Due to the high transition pressure,the BCC phase transition in copper competes with melting.In aluminum,the FCC-to-BCC transition is observed for all studied directions at pressures between 40 and 50 GPa far beyond the melting.In all considered cases we observe the coexistence of HCP and BCC phases during the FCC-to-BCC transition,which is consistent with the experimental data and atomistic calculations;this HCP phase forms in the course of accompanying plastic deformation with dislocation activity in the parent FCC phase.The plasticity incipience is also anisotropic in bothmetals,which is due to the difference in the projections of stress on the slip plane for different orientations of the FCC crystal.MD modeling results demonstrate a strong dependence of the FCC-to-BCC transition on the crystallographic direction,in which the material is loaded in the copper crystals.However,MD simulations data can only be obtained for specific points in the stereographic direction space;therefore,for more comprehensive understanding of the phase transition process,a feed-forward neural network was trained using MD modeling data.The trained machine learning model allowed us to construct continuous stereographic maps of phase transitions as a function of stress in the shock-compressed state of metal.Due to appearance and growth of multiple centers of new phase,the FCC-to-BCC transition leads to formation of a polycrystalline structure from the parent single crystal.展开更多
The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonal...The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonalization or quantum Monte Carlo simulations,particularly at finite temperatures.In this work,we propose a new algorithm for obtaining thermal pure quantum states,which allows efficient computation of both mechanical and thermodynamic properties at finite temperatures.We implement this algorithm in our open-source C++template library,Physica.Combining the improved algorithm with state-of-the-art software engineering,our implementation achieves high performance and numerical stability.As an example,we demonstrate that for the 4×4 Hubbard model,our method runs approximately 10~3times faster than HΦ3.5.2.Moreover,the accessible temperature range is extended down toβ=32 across arbitrary doping levels.These advances significantly push forward the frontiers of benchmarking for quantum many-body systems.展开更多
We present a comprehensive theoretical analysis of the general standard model(GSM),a recently proposed framework that unifies particle physics and cosmology within the gravitational quantum field theory(GQFT).Construc...We present a comprehensive theoretical analysis of the general standard model(GSM),a recently proposed framework that unifies particle physics and cosmology within the gravitational quantum field theory(GQFT).Constructed from first principles based exclusively on the intrinsic properties of leptons and quarks,the GSM reveals an enlarged gauge symmetry structure,WS_(c)(1,3)×GS(1)×Z_(2),which extends beyond the conventional U_(Y)(1)×SU_(L)(2)×SU_(C)(3) symmetry of the standard model.Here,WS_(c)(1,3) = SP(1,3)⋊W^(1,3)⋊SP_(c)(1,1) emerges as the conformal inhomogeneous spin gauge symmetry.Within GQFT,the GSM provides a consistent unification of the standard model of particle physics with cosmological models.It incorporates the four known fundamental interactions,electromagnetic,weak,strong,and gravitational,plus the Higgs scalar interaction,and also predicts novel interactions.These include spin gauge,chirality boost-spin gauge,chiral conformal-spin gauge,and scaling gauge forces,as well as additional scalar interactions.Furthermore,the GSM offers profound insights into the nature of gravity and spacetime and elucidates key mysteries of the dark side of the universe,such as the origins of dark matter,the dynamics of dark energy,and the physics of the early inflationary epoch.By establishing a new theoretical bridge between quantum field theory and general relativity,the GSM opens novel pathways for addressing long-standing challenges in fundamental physics.It provides a unified description of both fundamental interactions and cosmic evolution.展开更多
We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-...We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-2(SHANS2),a gas-filled recoil separator located at the China Accelerator Facility for Superheavy Elements(CAFE2).In total,20 decay chains are attributed to ^(288)Mc and 1 decay chain is assigned to ^(287)Mc.The measured oa-decay properties of ^(287,288)Mc as well as its descendants are consistent with the known data.No additional decay chains originating from the 2n or 5n reaction channels were detected.The excitation function of the ^(243)Am(^(48)Ca,3n)^(288)Mc reaction was measured at the cross-section level of picobarn,which indicates the promising capability for the study of heavy and superheavy nuclei at the facility.展开更多
The F_(1)-ATPase and V_(1)-ATPase are rotary biomotors.Alignment of their amino acid sequences,which originate from bovine heart mitochondria(1BMF)and Enterococcus hirae(3VR6),respectively,demonstrates that the segmen...The F_(1)-ATPase and V_(1)-ATPase are rotary biomotors.Alignment of their amino acid sequences,which originate from bovine heart mitochondria(1BMF)and Enterococcus hirae(3VR6),respectively,demonstrates that the segment forming the ATP catalytic pocket is highly conserved.Single-molecule experiments,however,have revealed subtle differences in efficiency between the F_(1) and V_(1) motors.Here,we perform both atomistic and coarse-grained molecular dynamics simulations to investigate the mechanochemical coupling and coordination in F_(1) and V_(1) ATPase.Our results show that the correlation between conformational changes in F_(1) is stronger than that in V_(1),indicating that the mechanochemical coupling in F_(1) is tighter than in V_(1).Moreover,the unidirectional rotation of F_(1) is more processive than that of V_(1),which accounts for the higher efficiency observed in F_(1) and explains the occasional backward steps detected in single-molecule experiments on V_(1).展开更多
Fig.3.(a)α-particle energy spectra,and(b)decay-time distributions on a logarithmic scale for the observed 288Mc and its descendant nuclei.In the panel(a),the red histograms show the observed full-energy events,while ...Fig.3.(a)α-particle energy spectra,and(b)decay-time distributions on a logarithmic scale for the observed 288Mc and its descendant nuclei.In the panel(a),the red histograms show the observed full-energy events,while the corresponding blue histograms show the reconstructed events.The red smooth curves in panel(b)are the expected time distributions according to the corresponding half-lives extracted from this work.展开更多
The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Th...The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Thus,the conventional SG experiment can be viewed as a magnetic-type spin effect.In this work,we successfully generalize the SG effect from magnetic-type to electric-type by solving Dirac's equation with a potential barrier,revealing an extraordinary spin effect.Beams of Dirac particles can be regarded as matter waves.Based on Dirac's equation,we obtain the explicit forms of the incident,reflected,and transmitted waves.The electric-type SG effect shows that the reflected and transmitted waves can exhibit notable spatial shifts,which depend on the spin direction and the incident angle of the wave.The electrictype SG effect has potential applications for separating Dirac particles with different spin directions and for estimating the spin direction of Dirac particles.Some discussions related to the interaction between spin and the electric field are also presented.展开更多
Investigations into first-order quantum phase transition(QPT)remain unclear in comparison to those of the second-order or continuous QPT,in which the order parameter and associated broken symmetry can be clearly ident...Investigations into first-order quantum phase transition(QPT)remain unclear in comparison to those of the second-order or continuous QPT,in which the order parameter and associated broken symmetry can be clearly identified and,at the same time,the concepts of universality class and critical scaling can be characterized by critical exponents.Here,we present a comparison study of these two kinds of QPT in the transverse Ising model;the emphasis is on the first-order QPT.In the absence of a longitudinal field,the ground state of the model exhibits a second-order QPT from the paramagnetic phase to the ferromagnetic phase,which is smeared out once the longitudinal field is applied.Surprisingly,the first excited state involves a firstorder QPT as the longitudinal field increases,which has not been reported in the literature.Within the framework of the pattern picture,we clearly identify the difference between these two kinds of QPT:for the continuous QPT,only the pattern flavoring the ferromagnetic phase is always dominant over the others.By contrast,there are at least two competitive patterns in the first-order QPT,which is further indicated by the patterns'occupancies,calculated by pattern projections on the ground-and first excited-state wavefunctions.Our results not only have a fundamental significance in the understanding of the nature of QPTs,but also a practical interest in quantum simulations used to test the present findings.展开更多
We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into e...We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into each spin in a history-dependent and trajectory-informed manner,the method effectively suppresses early freezing induced by inelastic boundaries and enhances the system's ability to explore complex energy landscapes.Numerical results on the maximum cut(MAX-CUT)instances of fully connected Sherrington–Kirkpatrick(SK)spin glass models,including the 2000-spin K_(2000)benchmark,demonstrate that the non-Markovian algorithm significantly improves both solution quality and convergence speed.Tests on randomly generated SK instances with 100 to 1000 spins further indicate favorable scalability and substantial gains in computational efficiency.Moreover,the proposed scheme is well suited for massively parallel hardware implementations,such as field-programmable gate arrays,providing a practical and scalable approach for solving large-scale combinatorial optimization problems.展开更多
The detection of gravitational waves by the LIGO-Virgo-KAGRA collaboration has ushered in a new era of observational astronomy,emphasizing the need for rapid and detailed parameter estimation and population-level anal...The detection of gravitational waves by the LIGO-Virgo-KAGRA collaboration has ushered in a new era of observational astronomy,emphasizing the need for rapid and detailed parameter estimation and population-level analyses.Traditional Bayesian inference methods,particularly Markov chain Monte Carlo,face significant computational challenges when dealing with the high-dimensional parameter spaces and complex noise characteristics inherent in gravitational wave data.This review examines the emerging role of simulation-based inference methods in gravitational wave astronomy,with a focus on approaches that leverage machine-learning techniques such as normalizing flows and neural posterior estimation.We provide a comprehensive overview of the theoretical foundations underlying various simulation-based inference methods,including neural posterior estimation,neural ratio estimation,neural likelihood estimation,flow matching,and consistency models.We explore the applications of these methods across diverse gravitational wave data processing scenarios,from single-source parameter estimation and overlapping signal analysis to testing general relativity and conducting population studies.Although these techniques demonstrate speed improvements over traditional methods in controlled studies,their model-dependent nature and sensitivity to prior assumptions are barriers to their widespread adoption.Their accuracy,which is similar to that of conventional methods,requires further validation across broader parameter spaces and noise conditions.展开更多
Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distribu...Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distributions over a wide range of neutron energies remains a challenge.In this study,a Bayesian neural network model was developed to predict the independent(IND)and cumulative fission yields of^(232)Th under neutron irradiation at various incident energies.To address the limited availability of experimental data for the analysis of IND mass distributions,we substituted mass-number-based yields with the yields of specific isotopes.Furthermore,physical phenomena or quantities,such as the odd-even effect and isospin,were introduced as constraints to enhance the physical consistency of the predictions.The impact of these constraints was evaluated using mass-chain yield distributions and their dependence on energy.Incorporating physical constraints significantly improves the prediction accuracy,yielding more reliable and physically meaningful fission yield data for nuclear physics and reactor design applications.展开更多
Following over 20 years of research,a direct measurement of the QGP temperature has been achieved at Relativistic Heavy-Ion Collider(RHIC),free from the blue-shift effect and contamination from strong interactions.Thi...Following over 20 years of research,a direct measurement of the QGP temperature has been achieved at Relativistic Heavy-Ion Collider(RHIC),free from the blue-shift effect and contamination from strong interactions.This viewpoint discusses a recent measurement of the QGP temperature at different stages at the Solenoidal Tracker at RHIC(STAR),which used e^(+)e^(-)pairs as penetrating probes.展开更多
The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in...The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in the extreme hot and dense hadronic environment emerging from proton–proton(pp)and heavy-ion collisions,where characteristic thermal energies exceed 100 MeV?A new femtoscopy analysis published on Nature[1]by the ALICE Collaboration at the Large Hadron Collider(LHC)delivers the clearest answer to date.展开更多
Based on the idea of treating the anti de Sitter(AdS)radius as a fixed parameter,we study the thermodynamics and topology of d-dimensional charged AdS black holes in the restricted phase space utilizing Visser's h...Based on the idea of treating the anti de Sitter(AdS)radius as a fixed parameter,we study the thermodynamics and topology of d-dimensional charged AdS black holes in the restricted phase space utilizing Visser's holographic approach.For the charged black hole with a cloud of strings and quintessence in the higher-dimensional spacetimes with d=(4,5,6),we demonstrate that the topological number remains invariant within the same canonical ensemble;however,a distinct topological number emerges in the grand canonical ensemble for the same black hole system.Notably,these results are independent of the dimension d and other related parameters.The formalism known as restricted phase space thermodynamics is checked in detail and some interesting thermodynamic behavior is revealed in the example case of d-dimensional charged AdS black holes with a cloud of strings and quintessence.This research lays the foundation for establishing a universal framework of restricted phase space thermodynamics and investigating its fundamental thermodynamic properties.展开更多
This study investigates the thermal and statistical properties of the Dirac oscillator within the framework of two prominent formulations of doubly special relativity(DSR):the Amelino-Camelia and Magueijo-Smolin model...This study investigates the thermal and statistical properties of the Dirac oscillator within the framework of two prominent formulations of doubly special relativity(DSR):the Amelino-Camelia and Magueijo-Smolin models.DSR extends Einstein's special relativity by introducing an additional invariant scale—the Planck energy—leading to modified energy-momentum relations that encode potential quantum-gravitational effects at ultra-high energies.In this context,we derive the modified Dirac equations for both DSR scenarios and analytically determine the corresponding energy spectra.These spectra are subsequently used to compute the partition function and key thermodynamic quantities,including specific heat,by employing the Euler-Maclaurin formula to facilitate an efficient approximation of the partition function.The analysis is restricted to the positive-energy sector,enabled by the exact Foldy-Wouthuysen transformation,which effectively decouples positive and negative energy states.The findings reveal that Planck-scale deformation parameters induce significant modifications in the energy spectrum and thermodynamic behavior of the Dirac oscillator in each DSR framework,thereby offering valuable insights into possible observable imprints of quantum gravitational phenomena in relativistic quantum systems.展开更多
The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor...The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor(QGT),another important concept in the field of quantum geometry.The DWZC is Hermitian with respect to the two integer indices,just like the original Hermitian WZC.Based on the symmetric logarithmic derivative operator,we propose a mixed-state quantum geometric tensor.Using the symmetric properties of the DWZC,we find that the real part of the QGT is connected to the real part of the DWZC and the square of eigenvalue differences of the density matrix,whereas the imaginary part can be given in terms of the imaginary part of the DWZC and the cube of the eigenvalue differences.For density matrices with full rank or no full rank,the QGT can be given in terms of real and imaginary parts of the DWZC.展开更多
Reservoir engineering has been widely used in various quantum technologies.Based on a cavity-QED(quantum electrodynamics)model,we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to o...Reservoir engineering has been widely used in various quantum technologies.Based on a cavity-QED(quantum electrodynamics)model,we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to optimize the performance of a quantum battery(QB)located inside a cavity driven by a broadband squeezed laser,which acts as a squeezed-vacuum reservoir.Using the reduced master equation of the QB obtained via the adiabatic elimination method,we focus on the QB's charging dynamics under tunable squeezed reservoirs governed by parametrically controlled squeezing parameters,which dictate the efficiency of energy transfer and the extractable work(ergotropy)of the QB.We show that increasing the squeezing strength improves the charging rate and enables rapid energy transfer,whereas the steady-state energy of the QB saturates at specific values of the squeezing parameter.Notably,the ergotropy of the QB reaches its maximum at a critical squeezing strength and does not scale monotonically with the squeezing strength.This nonmonotonic behavior underscores the existence of optimal parameter regimes,through which the performance of the QB can be significantly enhanced.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12135003,12122402,and 12475033)the National Key R&D Program of China(Grant No.2023YFE0109000)the Fundamental Research Funds for the Central Universities。
文摘The 19th century saw significant advancements in thermodynamics and the kinetic theory of gases,with J.C.Maxwell and L.E.Boltzmann playing key roles in the development of statistical physics through their work on the distribution of single-particle states.At the beginning of the 20th century,J.W.Gibbs established modern equilibrium statistical physics based on the statistical distribution of system microstates and the concept of ensembles.Subsequently,statistical physics expanded into the quantum and nonequilibrium domains.
基金supported by the National Key R&D Program of China(No.2023YFA1606701)the National Natural Science Foundation of China(Nos.12175042 and 12147101)。
文摘As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclear cluster physics.In this review,we briefly revisit the theoretical framework for calculating the reduced-width amplitude,as well as the outlines of cluster models to obtain microscopic or semi-microscopic cluster wave functions.We also introduce the recent progress related to cluster overlap amplitudes,including the implementation of cross-section estimation and extension to three-body clustering analysis.Comprehensive examples are provided to demonstrate the application of the reduced-width amplitude in analyzing clustering structures.
基金National Natural Science Foundation of China(11875039)Shanxi Scholarship Council of China(2023-033)+2 种基金Fundamental Research Program of Shanxi Province(202303021221071)China Baowu Low Carbon Metallurgical Innovation Foundation(2022)2023 Anhui Major Industrial Innovation Plan Project。
文摘The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result.
基金founded by the Ministry of Science and Higher Education of the Russian Federation,State assignments for research,registration No.1024032600084-8-1.3.2Study of the grain growth and the formation of polycrystalline structure as a result of phase transition(Section 6)was founded by the Russian Science Foundation,Project No.24-71-00078+3 种基金https://rscf.ru/en/project/24-71-00078/(accessed on 01 December 2025).Study of the orientation dependence of the phase transition of aluminum in Section 3 was founded by the Russian Science Foundation,Project No.24-19-00684https://rscf.ru/en/project/24-19-00684/(accessed on 01 December 2025).
文摘It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range of crystallographic directions of shock loading has not been revealed.In this work,we calculated the shock Hugoniot for aluminum and copper in different crystallographic directions([100],[110],[111],[112],[102],[114],[123],[134],[221]and[401])of shock compression using molecular dynamics(MD)simulations.The results showed a high pressure(>160 GPa for Cu and>40 GPa for Al)of the FCC-to-BCC transition.In copper,different characteristics of the phase transition are observed depending on the loading direction with the[100]compression direction being the weakest.The FCC-to-BCC transition for copper is in the range of 150–220 GPa,which is consistent with the existing experimental data.Due to the high transition pressure,the BCC phase transition in copper competes with melting.In aluminum,the FCC-to-BCC transition is observed for all studied directions at pressures between 40 and 50 GPa far beyond the melting.In all considered cases we observe the coexistence of HCP and BCC phases during the FCC-to-BCC transition,which is consistent with the experimental data and atomistic calculations;this HCP phase forms in the course of accompanying plastic deformation with dislocation activity in the parent FCC phase.The plasticity incipience is also anisotropic in bothmetals,which is due to the difference in the projections of stress on the slip plane for different orientations of the FCC crystal.MD modeling results demonstrate a strong dependence of the FCC-to-BCC transition on the crystallographic direction,in which the material is loaded in the copper crystals.However,MD simulations data can only be obtained for specific points in the stereographic direction space;therefore,for more comprehensive understanding of the phase transition process,a feed-forward neural network was trained using MD modeling data.The trained machine learning model allowed us to construct continuous stereographic maps of phase transitions as a function of stress in the shock-compressed state of metal.Due to appearance and growth of multiple centers of new phase,the FCC-to-BCC transition leads to formation of a polycrystalline structure from the parent single crystal.
基金Fu-Zhou Chen for helpful discussions.The work is partly supported by the National Key Research and Development Program of China(Grant No.2022YFA1402704)the National Natural Science Foundation of China(Grant No.12247101)。
文摘The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonalization or quantum Monte Carlo simulations,particularly at finite temperatures.In this work,we propose a new algorithm for obtaining thermal pure quantum states,which allows efficient computation of both mechanical and thermodynamic properties at finite temperatures.We implement this algorithm in our open-source C++template library,Physica.Combining the improved algorithm with state-of-the-art software engineering,our implementation achieves high performance and numerical stability.As an example,we demonstrate that for the 4×4 Hubbard model,our method runs approximately 10~3times faster than HΦ3.5.2.Moreover,the accessible temperature range is extended down toβ=32 across arbitrary doping levels.These advances significantly push forward the frontiers of benchmarking for quantum many-body systems.
基金supported by the National Key Research and Development Program of China (Grant No.2020YFC2201501)the National Natural Science Foundation of China (Grant Nos.12547104,12441504,12147103 and 11821505)the Strategic Priority Research Program of the Chinese Academy of Sciences。
文摘We present a comprehensive theoretical analysis of the general standard model(GSM),a recently proposed framework that unifies particle physics and cosmology within the gravitational quantum field theory(GQFT).Constructed from first principles based exclusively on the intrinsic properties of leptons and quarks,the GSM reveals an enlarged gauge symmetry structure,WS_(c)(1,3)×GS(1)×Z_(2),which extends beyond the conventional U_(Y)(1)×SU_(L)(2)×SU_(C)(3) symmetry of the standard model.Here,WS_(c)(1,3) = SP(1,3)⋊W^(1,3)⋊SP_(c)(1,1) emerges as the conformal inhomogeneous spin gauge symmetry.Within GQFT,the GSM provides a consistent unification of the standard model of particle physics with cosmological models.It incorporates the four known fundamental interactions,electromagnetic,weak,strong,and gravitational,plus the Higgs scalar interaction,and also predicts novel interactions.These include spin gauge,chirality boost-spin gauge,chiral conformal-spin gauge,and scaling gauge forces,as well as additional scalar interactions.Furthermore,the GSM offers profound insights into the nature of gravity and spacetime and elucidates key mysteries of the dark side of the universe,such as the origins of dark matter,the dynamics of dark energy,and the physics of the early inflationary epoch.By establishing a new theoretical bridge between quantum field theory and general relativity,the GSM opens novel pathways for addressing long-standing challenges in fundamental physics.It provides a unified description of both fundamental interactions and cosmic evolution.
基金supported in part by the National Key R&D Program of China (Contract Nos.2023YFA1606500,2024YFE0109800,and 2024YFE0110400)Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB34010000)+5 种基金the Gansu Key Project of Science and Technology (Grant No.23ZDGA014)the Guangdong Major Project of Basic and Applied Basic Research (Grant No.2021B0301030006)the National Natural Science Foundation of China (Grant Nos.12105328,W2412040,12475126,12422507,12035011,12375118,12435008,and W2412043)the Chinese Academy of Sciences Project for Young Scientists in Basic Research(Grant No.YSBR-002)the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant Nos.2020409 and 2023439)the Russian Science Foundation (Grant No.25-42-00003)。
文摘We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-2(SHANS2),a gas-filled recoil separator located at the China Accelerator Facility for Superheavy Elements(CAFE2).In total,20 decay chains are attributed to ^(288)Mc and 1 decay chain is assigned to ^(287)Mc.The measured oa-decay properties of ^(287,288)Mc as well as its descendants are consistent with the known data.No additional decay chains originating from the 2n or 5n reaction channels were detected.The excitation function of the ^(243)Am(^(48)Ca,3n)^(288)Mc reaction was measured at the cross-section level of picobarn,which indicates the promising capability for the study of heavy and superheavy nuclei at the facility.
基金supported by the National Natural Science Foundation of China(Grant Nos.22193032 and 32401033)the Research Fund of Wenzhou Institute,Chinese Academy of Sciences(Grant Nos.WIUCASQD2020009,WIUCASQD2023005,XSZD2024004,2021HZSY0061,and WIUCASICTP2022)。
文摘The F_(1)-ATPase and V_(1)-ATPase are rotary biomotors.Alignment of their amino acid sequences,which originate from bovine heart mitochondria(1BMF)and Enterococcus hirae(3VR6),respectively,demonstrates that the segment forming the ATP catalytic pocket is highly conserved.Single-molecule experiments,however,have revealed subtle differences in efficiency between the F_(1) and V_(1) motors.Here,we perform both atomistic and coarse-grained molecular dynamics simulations to investigate the mechanochemical coupling and coordination in F_(1) and V_(1) ATPase.Our results show that the correlation between conformational changes in F_(1) is stronger than that in V_(1),indicating that the mechanochemical coupling in F_(1) is tighter than in V_(1).Moreover,the unidirectional rotation of F_(1) is more processive than that of V_(1),which accounts for the higher efficiency observed in F_(1) and explains the occasional backward steps detected in single-molecule experiments on V_(1).
文摘Fig.3.(a)α-particle energy spectra,and(b)decay-time distributions on a logarithmic scale for the observed 288Mc and its descendant nuclei.In the panel(a),the red histograms show the observed full-energy events,while the corresponding blue histograms show the reconstructed events.The red smooth curves in panel(b)are the expected time distributions according to the corresponding half-lives extracted from this work.
基金supported by the Quantum Science and Technology-National Science and Technology Major Project of China(Grant No.2024ZD0301000)the National Natural Science Foundation of China(Grant No.12275136)。
文摘The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Thus,the conventional SG experiment can be viewed as a magnetic-type spin effect.In this work,we successfully generalize the SG effect from magnetic-type to electric-type by solving Dirac's equation with a potential barrier,revealing an extraordinary spin effect.Beams of Dirac particles can be regarded as matter waves.Based on Dirac's equation,we obtain the explicit forms of the incident,reflected,and transmitted waves.The electric-type SG effect shows that the reflected and transmitted waves can exhibit notable spatial shifts,which depend on the spin direction and the incident angle of the wave.The electrictype SG effect has potential applications for separating Dirac particles with different spin directions and for estimating the spin direction of Dirac particles.Some discussions related to the interaction between spin and the electric field are also presented.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFA1402704)the National Natural Science Foundation of China(Grant No.12247101)。
文摘Investigations into first-order quantum phase transition(QPT)remain unclear in comparison to those of the second-order or continuous QPT,in which the order parameter and associated broken symmetry can be clearly identified and,at the same time,the concepts of universality class and critical scaling can be characterized by critical exponents.Here,we present a comparison study of these two kinds of QPT in the transverse Ising model;the emphasis is on the first-order QPT.In the absence of a longitudinal field,the ground state of the model exhibits a second-order QPT from the paramagnetic phase to the ferromagnetic phase,which is smeared out once the longitudinal field is applied.Surprisingly,the first excited state involves a firstorder QPT as the longitudinal field increases,which has not been reported in the literature.Within the framework of the pattern picture,we clearly identify the difference between these two kinds of QPT:for the continuous QPT,only the pattern flavoring the ferromagnetic phase is always dominant over the others.By contrast,there are at least two competitive patterns in the first-order QPT,which is further indicated by the patterns'occupancies,calculated by pattern projections on the ground-and first excited-state wavefunctions.Our results not only have a fundamental significance in the understanding of the nature of QPTs,but also a practical interest in quantum simulations used to test the present findings.
基金supported by the National Key Research and Development Program of China(Grant No.2024YFA1408500)the National Natural Science Foundation of China(Grant Nos.12174028 and 12574115)the Open Fund of the State Key Laboratory of Spintronics Devices and Technologies(Grant No.SPL-2408)。
文摘We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into each spin in a history-dependent and trajectory-informed manner,the method effectively suppresses early freezing induced by inelastic boundaries and enhances the system's ability to explore complex energy landscapes.Numerical results on the maximum cut(MAX-CUT)instances of fully connected Sherrington–Kirkpatrick(SK)spin glass models,including the 2000-spin K_(2000)benchmark,demonstrate that the non-Markovian algorithm significantly improves both solution quality and convergence speed.Tests on randomly generated SK instances with 100 to 1000 spins further indicate favorable scalability and substantial gains in computational efficiency.Moreover,the proposed scheme is well suited for massively parallel hardware implementations,such as field-programmable gate arrays,providing a practical and scalable approach for solving large-scale combinatorial optimization problems.
基金supported by the National Key Research and Development Program of China(2021YFC2203004)the National Natural Science Foundation of China(NSFC)(12405076,12247187,and 12147103)+1 种基金the National Astronomical Data Center(NADC2023YDS-01)the Fundamental Research Funds for the Central Universities.
文摘The detection of gravitational waves by the LIGO-Virgo-KAGRA collaboration has ushered in a new era of observational astronomy,emphasizing the need for rapid and detailed parameter estimation and population-level analyses.Traditional Bayesian inference methods,particularly Markov chain Monte Carlo,face significant computational challenges when dealing with the high-dimensional parameter spaces and complex noise characteristics inherent in gravitational wave data.This review examines the emerging role of simulation-based inference methods in gravitational wave astronomy,with a focus on approaches that leverage machine-learning techniques such as normalizing flows and neural posterior estimation.We provide a comprehensive overview of the theoretical foundations underlying various simulation-based inference methods,including neural posterior estimation,neural ratio estimation,neural likelihood estimation,flow matching,and consistency models.We explore the applications of these methods across diverse gravitational wave data processing scenarios,from single-source parameter estimation and overlapping signal analysis to testing general relativity and conducting population studies.Although these techniques demonstrate speed improvements over traditional methods in controlled studies,their model-dependent nature and sensitivity to prior assumptions are barriers to their widespread adoption.Their accuracy,which is similar to that of conventional methods,requires further validation across broader parameter spaces and noise conditions.
基金supported by the National Natural Science Foundation of China(Nos.12247126 and 12375123)Henan Postdoctoral Foundation(No.HN2024013)the Natural Science Foundation of Henan Province(No.242300421048)。
文摘Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distributions over a wide range of neutron energies remains a challenge.In this study,a Bayesian neural network model was developed to predict the independent(IND)and cumulative fission yields of^(232)Th under neutron irradiation at various incident energies.To address the limited availability of experimental data for the analysis of IND mass distributions,we substituted mass-number-based yields with the yields of specific isotopes.Furthermore,physical phenomena or quantities,such as the odd-even effect and isospin,were introduced as constraints to enhance the physical consistency of the predictions.The impact of these constraints was evaluated using mass-chain yield distributions and their dependence on energy.Incorporating physical constraints significantly improves the prediction accuracy,yielding more reliable and physically meaningful fission yield data for nuclear physics and reactor design applications.
文摘Following over 20 years of research,a direct measurement of the QGP temperature has been achieved at Relativistic Heavy-Ion Collider(RHIC),free from the blue-shift effect and contamination from strong interactions.This viewpoint discusses a recent measurement of the QGP temperature at different stages at the Solenoidal Tracker at RHIC(STAR),which used e^(+)e^(-)pairs as penetrating probes.
基金supported in part by the National Key Research and Development Project of China(No.2024YFA1612500)the National Natural Science Foundation of China(Nos.12422509,12375121,12547102)。
文摘The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in the extreme hot and dense hadronic environment emerging from proton–proton(pp)and heavy-ion collisions,where characteristic thermal energies exceed 100 MeV?A new femtoscopy analysis published on Nature[1]by the ALICE Collaboration at the Large Hadron Collider(LHC)delivers the clearest answer to date.
基金supported by the Natural Science Foundation of Shanxi Province(202303021211180)the Program of State Key Laboratory of Quantum Optics and Quantum Optics Devices(KF202403)。
文摘Based on the idea of treating the anti de Sitter(AdS)radius as a fixed parameter,we study the thermodynamics and topology of d-dimensional charged AdS black holes in the restricted phase space utilizing Visser's holographic approach.For the charged black hole with a cloud of strings and quintessence in the higher-dimensional spacetimes with d=(4,5,6),we demonstrate that the topological number remains invariant within the same canonical ensemble;however,a distinct topological number emerges in the grand canonical ensemble for the same black hole system.Notably,these results are independent of the dimension d and other related parameters.The formalism known as restricted phase space thermodynamics is checked in detail and some interesting thermodynamic behavior is revealed in the example case of d-dimensional charged AdS black holes with a cloud of strings and quintessence.This research lays the foundation for establishing a universal framework of restricted phase space thermodynamics and investigating its fundamental thermodynamic properties.
基金funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan,Program No.BR24992759。
文摘This study investigates the thermal and statistical properties of the Dirac oscillator within the framework of two prominent formulations of doubly special relativity(DSR):the Amelino-Camelia and Magueijo-Smolin models.DSR extends Einstein's special relativity by introducing an additional invariant scale—the Planck energy—leading to modified energy-momentum relations that encode potential quantum-gravitational effects at ultra-high energies.In this context,we derive the modified Dirac equations for both DSR scenarios and analytically determine the corresponding energy spectra.These spectra are subsequently used to compute the partition function and key thermodynamic quantities,including specific heat,by employing the Euler-Maclaurin formula to facilitate an efficient approximation of the partition function.The analysis is restricted to the positive-energy sector,enabled by the exact Foldy-Wouthuysen transformation,which effectively decouples positive and negative energy states.The findings reveal that Planck-scale deformation parameters induce significant modifications in the energy spectrum and thermodynamic behavior of the Dirac oscillator in each DSR framework,thereby offering valuable insights into possible observable imprints of quantum gravitational phenomena in relativistic quantum systems.
基金Project supported by Quantum Science and Technology–National Science and Technology Major Project(Grant No.2024ZD0301000)the National Natural Science Foundation of China(Grant No.12305031)+1 种基金the Hangzhou Joint Fund of the Natural Science Foundation of Zhejiang Province,China(Grant No.LHZSD24A050001)the Science Foundation of Zhejiang Sci-Tech University(Grant Nos.23062088Y and 23062153-Y)。
文摘The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor(QGT),another important concept in the field of quantum geometry.The DWZC is Hermitian with respect to the two integer indices,just like the original Hermitian WZC.Based on the symmetric logarithmic derivative operator,we propose a mixed-state quantum geometric tensor.Using the symmetric properties of the DWZC,we find that the real part of the QGT is connected to the real part of the DWZC and the square of eigenvalue differences of the density matrix,whereas the imaginary part can be given in terms of the imaginary part of the DWZC and the cube of the eigenvalue differences.For density matrices with full rank or no full rank,the QGT can be given in terms of real and imaginary parts of the DWZC.
基金supported by the National Natural Science Foundation of China(Grants No.12274422)the Natural Science Foundation of Hubei Province(Grant No.2022CFA013)support from A*STAR(Grant Nos.C230917003 and C230917007)。
文摘Reservoir engineering has been widely used in various quantum technologies.Based on a cavity-QED(quantum electrodynamics)model,we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to optimize the performance of a quantum battery(QB)located inside a cavity driven by a broadband squeezed laser,which acts as a squeezed-vacuum reservoir.Using the reduced master equation of the QB obtained via the adiabatic elimination method,we focus on the QB's charging dynamics under tunable squeezed reservoirs governed by parametrically controlled squeezing parameters,which dictate the efficiency of energy transfer and the extractable work(ergotropy)of the QB.We show that increasing the squeezing strength improves the charging rate and enables rapid energy transfer,whereas the steady-state energy of the QB saturates at specific values of the squeezing parameter.Notably,the ergotropy of the QB reaches its maximum at a critical squeezing strength and does not scale monotonically with the squeezing strength.This nonmonotonic behavior underscores the existence of optimal parameter regimes,through which the performance of the QB can be significantly enhanced.
