We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful ...We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful probability and fidelity of the four schemes reach 1. In the first two schemes, the receiver can only apply one of the unitary transformations to reconstruct the original state, making it easier for these two schemes to be directly realized. In the third and fourth schemes, the sender can preform Bell-state measurements instead of multipartite entanglement measurements of the existing similar schemes, which makes real experiments more suitable. It is found that the last three schemes may become tripartite controlled teleportation schemes of teleporting an arbitrary multi-particle state after a simple modification. Finally, we present a new scheme for three-party sharing an arbitrary unknown multi-particle state. In this scheme, the sender first shares three three-particle GHZ states with two agents. After setting up the secure quantum channel, an arbitrary unknown multi-particle state can be perfectly teleported if the sender performs three Bell-state measurements, and either of two receivers operates an appropriate unitary transformation to obtain the original state with the help of other receiver's three single-particle measurements. The successful probability and fidelity of this scheme also reach 1. It is demonstrated that this scheme can be generalized easily to the case of sharing an arbitrary unknown multi-particle state among several agents.展开更多
The general scheme for teleportation of a multi-particle d-level quantumstate is presented when m pairs of partially entangled particles are utilized as quantum channels.The probabilistic teleportation can be achieved...The general scheme for teleportation of a multi-particle d-level quantumstate is presented when m pairs of partially entangled particles are utilized as quantum channels.The probabilistic teleportation can be achieved with a successful probability of Π from N=0 to d-1of (C_0~N)~2/d~M, which is determined by the smallest coefficients of each entangled channels.展开更多
Entanglement swapping is a key technology for multi-hop communication based on entanglement in quantum networks. However, the end-to-end delay of the traditional sequential entanglement swapping (SEQES) grows rapidly ...Entanglement swapping is a key technology for multi-hop communication based on entanglement in quantum networks. However, the end-to-end delay of the traditional sequential entanglement swapping (SEQES) grows rapidly withthe increase of network scale. To solve this problem, we first propose a low-delay multi-particle simultaneous entanglementswapping (SES) scheme to establish the remote four-particle Greenberger–Horne–Zeilinger (GHZ) channel states for thebidirectional teleportation of three-particle GHZ states, in which the intermediate nodes perform Bell state measurements,send the measurement results and the Bell state type to the user node Bob (or Alice) through classical channel simultaneously. Bob (or Alice) only needs to carry out a proper unitary operation according to the information he (or she) hasreceived. Further, we put forward a hierarchical simultaneous entanglement swapping (HSES) scheme to reduce the classical information transmission cost, which is composed of level-1 SES and level-2 SES (schemes). The former is an innersegment SES, and the latter is an inter segments SES. Theoretical analysis and simulation results show the HSES can obtainthe optimal performance tradeoff between end-to-end delay and classical cost.展开更多
Entanglement, the Einstein-Podolsky Rosen (EPR) paradox and Bell's failure of local-hidden- variable (LHV) theories are three historically famous forms of "quantum nonlocality". We give experimental criteria fo...Entanglement, the Einstein-Podolsky Rosen (EPR) paradox and Bell's failure of local-hidden- variable (LHV) theories are three historically famous forms of "quantum nonlocality". We give experimental criteria for these three forms of nonlocality in multi-particle systems, with the aim of better understanding the transition from microscopic to macroscopic nonlocality. We examine the nonlocality of N separated spin J systems. First, we obtain multipartite Bell inequalities that address the correlation between spin values measured at each site, and then we review spin squeezing inequal- ities that address the degree of reduction in the variance of collective spins. The latter have been particularly useful as a tool for investigating entanglement in Bose Einstein eondensates (BEC). We present solutions for two topical quantum states: multi-qubit Greenberger-Horne Zeilinger (GHZ) states, and the ground state of a two-well BEC.展开更多
We propose a scheme for robustly storing multi-atom entangled states involving Bell states, three-particle W-state, n-particle W-like-states, generalized multi-particle W-states, n-particle GHZ-states, and partially e...We propose a scheme for robustly storing multi-atom entangled states involving Bell states, three-particle W-state, n-particle W-like-states, generalized multi-particle W-states, n-particle GHZ-states, and partially entangled states in cavity QED. Our scheme can preserve the internal structure of the entangled states above, with only generation of a global phase corresponding to each of entangled states during the storage of them. One single-mode cavity and n identical two-level atoms are required. Our scheme may be realized in the present technology. The idea may be also utilized to store multi-trapped-ion entangled states in linear ion trap.展开更多
Using bi-spinor fields we write the pseudo-scalar and bi-spinor fields that are characterized by the field functions of coordinates of several particles, namely multi-particle fields. By applying the quantization proc...Using bi-spinor fields we write the pseudo-scalar and bi-spinor fields that are characterized by the field functions of coordinates of several particles, namely multi-particle fields. By applying the quantization procedure to these multi-particle fields, hadronic creation and annihilation operators have been obtained.展开更多
Turing patterns are typical spatiotemporal ordered structures in various systems driven far from thermodynamic equilibrium.Turing’s reaction-diffusion theory,containing a long-range inhibiting agent and a local catal...Turing patterns are typical spatiotemporal ordered structures in various systems driven far from thermodynamic equilibrium.Turing’s reaction-diffusion theory,containing a long-range inhibiting agent and a local catalytic agent,has provided an explanation for the formation of some patterns in nature.Numerical,experimental and theoretical studies about Turing/Turing-like patterns have been generally focused on systems driven far from thermodynamic equilibrium.The local dynamics of these systems are commonly very complex,which brings great difficulties to understanding of formation of patterns.Here,we investigate a type of Turing-like patterns in a near-equilibrium thermodynamic system experimentally and theoretically,and put forward a new formation mechanism and a quantitative method for Turing/Turing-like patterns.Specifically,we observe a type of Turing-like patterns in starch solutions,and study the effect of concentration on the structure of patterns.The experimental results show that,with the increase of concentration,patterns change from spots to inverse spots,and labyrinthine stripe patterns appear in the region of intermediate concentration.We analyze and model the formation mechanism of these patterns observed in experiments,and the simulation results agree with the experimental results.Our conclusion indicates that the random aggregation of spatial components leads to formation of these patterns,and the proportion of spatial components determines the structures.Our findings shed light on the formation mechanism for Turing/Turing-like patterns.展开更多
In most probabilistic teleportation schemes, if the teleportation fails, the unknown quantum state will be completely ruined. In addition, the frequently proposed high-dimensional unitary operations are very difficult...In most probabilistic teleportation schemes, if the teleportation fails, the unknown quantum state will be completely ruined. In addition, the frequently proposed high-dimensional unitary operations are very difficult to realize experimentally. To maintain the integrity of the unknown quantum state to be teleported, this analysis does not focus attention on the original multi-particle state but seeks to construct a faithful channel with an ancillary particle and a unified high-dimensional unitary operation. The result shows that if the construction of the multi-group Einstein-Podolsky-Rosen pair succeeds, the original multi-particle state can be used to deterministically teleport the unknown quantum state of the entangled multiple particles which avoids undermining the integrity of the unknown state brought about by failure. This unified high-dimensional operation is appealing due to the obvious experimental convenience.展开更多
For measurement of sediment spatial concentration of nearshore seawater, a turbid water system with several. kinds of particles is investigated from the viewpoint of the characteristics of particles. Firstly, the clas...For measurement of sediment spatial concentration of nearshore seawater, a turbid water system with several. kinds of particles is investigated from the viewpoint of the characteristics of particles. Firstly, the classical physical and chemical conductivity formula is extended to macro-particle (such as sand) conductivity formula. Secondly, the Fricke formula suitable for only one kind of particles is extended to the conductivity formula suitable for several kinds of particles.. Finally, the multi-particle conductivity formula is applied to the measurement of sediment spatial concentration.展开更多
Lithium-ion batteries have been rapidly developed as clean energy sources in many industrial fields,such as new energy vehicles and energy storage.The core issues hindering their further promotion and application are ...Lithium-ion batteries have been rapidly developed as clean energy sources in many industrial fields,such as new energy vehicles and energy storage.The core issues hindering their further promotion and application are reliability and safety.A digital twin model that maps onto the physical entity of the battery with high simulation accuracy helps to monitor internal states and improve battery safety.This work focuses on developing a digital twin model via a mechanism-data-driven parameter updating algorithm to increase the simulation accuracy of the internal and external characteristics of the full-time domain battery under complex working conditions.An electrochemical model is first developed with the consideration of how electrode particle size impacts battery characteristics.By adding the descriptions of temperature distribution and particle-level stress,a multi-particle size electrochemical-thermal-mechanical coupling model is established.Then,considering the different electrical and thermal effect among individual cells,a model for the battery pack is constructed.A digital twin model construction method is finally developed and verified with battery operating data.展开更多
There exist interactions among pedestrians and between pedestrian and environment in evacuation. These interactions include attraction, repulsion and friction that play key roles in human evacuation behaviors, speed a...There exist interactions among pedestrians and between pedestrian and environment in evacuation. These interactions include attraction, repulsion and friction that play key roles in human evacuation behaviors, speed and efficiency. Most former evacuation models focus on the attraction force, while repulsion and friction are not well modeled. As a kind of multi-particle self-driven model, the social force model introduced in recent years can represent those three forces but with low simulation efficiency because it is a continuous model with complex rules. Discrete models such as the cellular automata model and the lattice gas model have simple rules and high simulation efficiency, but are not quite suitable for interactions’ simulation. In this paper, a new cellular automata model based on traditional models is introduced in which repulsion and friction are modeled quantitatively. It is indicated that the model can simulate some basic behaviors, e.g. arching and the “faster-is-slower” phenomenon, in evacuation as multi-particle self-driven models, but with high efficiency as the normal cellular automata model and the lattice gas model.展开更多
Radiative cooling can achieve cooling effect without consuming any energy by delivering energy into outer space(3K) through"atmospheric window"(8–13 μm). Conventional radiative cooling coating with multi-l...Radiative cooling can achieve cooling effect without consuming any energy by delivering energy into outer space(3K) through"atmospheric window"(8–13 μm). Conventional radiative cooling coating with multi-layer structure was severely restricted during application due to its complex preparation process and high cost. In this study, a single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles was proposed. The algorithm for calculating the radiative properties of the multi-particle system was developed. Monte Carlo ray-tracing method combined with that algorithm was used to solve the radiative transfer equation(RTE) of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles.The effects of particle diameter, volume fraction and coating thickness on radiative cooling performance were analyzed to obtain the best radiative cooling performance. The numerical results indicated that the average reflectivity of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles in the solar spectrum can reach 95.6%, while and the average emissivity in the "atmospheric window" spectrum can reach 94.9% without additional silver-reflectance layer. The average reflectivity in the solar spectrum and average emissivity in the "atmospheric window" spectrum of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles can increase 4.6% and 4.8% compared to the double-layer radiative cooling coating. This numerical research results can provide a theoretical guidance for design and optimization of single-layer radiative cooling coatings containing mixed nanoparticles.展开更多
Teleportation schemes based on probabilistic channels usually rely heavily on the implementation of high-dimensional unitary operations. Since high-dimensional unitary operations are very difficult to directly impleme...Teleportation schemes based on probabilistic channels usually rely heavily on the implementation of high-dimensional unitary operations. Since high-dimensional unitary operations are very difficult to directly implement in physics experiments, methods are used to avoid high-dimensional unitary operations during the teleportation process. This paper describes how to construct a deterministic teleportation channel and a control channel using Bell state measurements only instead of high-dimensional unitary operations. Here, the general four-particle and five-particle class states are used as the potential quantum channel and the control channel for deterministic teleportation even without access to the relevant parameters. The results show that this scheme makes physical realization of teleportation more reasonable.展开更多
The level structures of 93 Mo are investigated using Large Scale Shell Model calculations,and reasonable agreement is obtained between the experimental and calculated values.The calculated results show that the lower-...The level structures of 93 Mo are investigated using Large Scale Shell Model calculations,and reasonable agreement is obtained between the experimental and calculated values.The calculated results show that the lower-lying states are mainly dominated by proton excitations from the If5/2,2 p3/2,and 2 p1/2 orbitals into the higher orbitals across the Z=38 or Z=40 subshell closure.For the higher-spin states,multi-particle excitations,including the excitation of 2 d5/2 neutrons across the N=56 subshell closure into the high-j intruder 1 h11/2 orbital,are essential.Moreover,the previously unknown spin-parity assignments of the six higher excited states in 93 Mo are inferred from the shell model calculations.展开更多
Space-charge forces acting in mismatched beams have been identified as a major cause of beam halo. In this paper,we describe the beam halo experimental results in a FODO beam line at IHEP. With this beam transport lin...Space-charge forces acting in mismatched beams have been identified as a major cause of beam halo. In this paper,we describe the beam halo experimental results in a FODO beam line at IHEP. With this beam transport line, experiments are carried out to compare the measured data with the multi-particle simulations and to study the formation of a beam halo. The maximum measured amplitudes of the matched and mismatched beam profiles agree well with simulations. Details of the experiment are presented.展开更多
A new approach for tree-level amplitudes with multiple fermion lines is presented.It primarily focuses on the simplification of fermion lines.By calculating two vectors recursively without any matrix multiplications,t...A new approach for tree-level amplitudes with multiple fermion lines is presented.It primarily focuses on the simplification of fermion lines.By calculating two vectors recursively without any matrix multiplications,the result of a fermion line is reduced to a very compact form depending only on the two vectors.Comparisons with other packages are presented,and the results show that our package FDC provides a very good performance in the processes of multiple fermion lines with this new approach and some other improvements.A further comparison with WHIZARD shows that this new approach has a competitive efficiency in computing pure amplitude squares without phase space integration.展开更多
Laser cooling of Li-like C^3+and O^4+relativistic heavy ion beams is planned at the experimental Cooler Storage Ring(CSRe). Recently, a preparatory experiment to test important prerequisites for laser cooling of r...Laser cooling of Li-like C^3+and O^4+relativistic heavy ion beams is planned at the experimental Cooler Storage Ring(CSRe). Recently, a preparatory experiment to test important prerequisites for laser cooling of relativistic^12C^3+ion beams using a pulsed laser system has been performed at the CSRe. Unfortunately, the interaction between the ions and the pulsed laser cannot be detected. In order to study the laser cooling process and find the optimized parameters for future laser cooling experiments, a multi-particle tracking method has been developed to simulate the detailed longitudinal dynamics of laser-cooled ion beams at the CSRe. Simulations of laser cooling of the^12C^3+ion beams by scanning the frequency of the RF-buncher or continuous wave(CW) laser wavelength have been performed. The simulation results indicate that ion beams with a large momentum spread could be laser-cooled by the combination of only one CW laser and the RF-buncher, and show the requirements of a successful laser cooling experiment. The optimized parameters for scanning the RF-buncher frequency or laser frequency have been obtained.Furthermore, the heating effects have been estimated for laser cooling at the CSRe. The Schottky noise spectra of longitudinally modulated and laser-cooled ion beams have been simulated to fully explain and anticipate the experimental results. The combination of Schottky spectra from the highly sensitive resonant Schottky pick-up and the simulation methods developed in this paper will be helpful to investigate the longitudinal dynamics of RF-bunched and ultra-cold ion beams in the upcoming laser cooling experiments at the CSRe.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 11071178)
文摘We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful probability and fidelity of the four schemes reach 1. In the first two schemes, the receiver can only apply one of the unitary transformations to reconstruct the original state, making it easier for these two schemes to be directly realized. In the third and fourth schemes, the sender can preform Bell-state measurements instead of multipartite entanglement measurements of the existing similar schemes, which makes real experiments more suitable. It is found that the last three schemes may become tripartite controlled teleportation schemes of teleporting an arbitrary multi-particle state after a simple modification. Finally, we present a new scheme for three-party sharing an arbitrary unknown multi-particle state. In this scheme, the sender first shares three three-particle GHZ states with two agents. After setting up the secure quantum channel, an arbitrary unknown multi-particle state can be perfectly teleported if the sender performs three Bell-state measurements, and either of two receivers operates an appropriate unitary transformation to obtain the original state with the help of other receiver's three single-particle measurements. The successful probability and fidelity of this scheme also reach 1. It is demonstrated that this scheme can be generalized easily to the case of sharing an arbitrary unknown multi-particle state among several agents.
文摘The general scheme for teleportation of a multi-particle d-level quantumstate is presented when m pairs of partially entangled particles are utilized as quantum channels.The probabilistic teleportation can be achieved with a successful probability of Π from N=0 to d-1of (C_0~N)~2/d~M, which is determined by the smallest coefficients of each entangled channels.
基金Project supported by the National Natural Science Foundation of China(Grant No.61971348)the Scientific Research Program Funded by Shaanxi Provincial Education Department,China(Grant No.16JK1711)the Natural Science Foundation Research Project of Shaanxi Province,China(Grant No.2016JQ6033).
文摘Entanglement swapping is a key technology for multi-hop communication based on entanglement in quantum networks. However, the end-to-end delay of the traditional sequential entanglement swapping (SEQES) grows rapidly withthe increase of network scale. To solve this problem, we first propose a low-delay multi-particle simultaneous entanglementswapping (SES) scheme to establish the remote four-particle Greenberger–Horne–Zeilinger (GHZ) channel states for thebidirectional teleportation of three-particle GHZ states, in which the intermediate nodes perform Bell state measurements,send the measurement results and the Bell state type to the user node Bob (or Alice) through classical channel simultaneously. Bob (or Alice) only needs to carry out a proper unitary operation according to the information he (or she) hasreceived. Further, we put forward a hierarchical simultaneous entanglement swapping (HSES) scheme to reduce the classical information transmission cost, which is composed of level-1 SES and level-2 SES (schemes). The former is an innersegment SES, and the latter is an inter segments SES. Theoretical analysis and simulation results show the HSES can obtainthe optimal performance tradeoff between end-to-end delay and classical cost.
文摘Entanglement, the Einstein-Podolsky Rosen (EPR) paradox and Bell's failure of local-hidden- variable (LHV) theories are three historically famous forms of "quantum nonlocality". We give experimental criteria for these three forms of nonlocality in multi-particle systems, with the aim of better understanding the transition from microscopic to macroscopic nonlocality. We examine the nonlocality of N separated spin J systems. First, we obtain multipartite Bell inequalities that address the correlation between spin values measured at each site, and then we review spin squeezing inequal- ities that address the degree of reduction in the variance of collective spins. The latter have been particularly useful as a tool for investigating entanglement in Bose Einstein eondensates (BEC). We present solutions for two topical quantum states: multi-qubit Greenberger-Horne Zeilinger (GHZ) states, and the ground state of a two-well BEC.
基金The project partially supported by Natural Science Foundation of Hunan Province of China under Grant No. 05JJ30005, the Science Research Fund of Educational Department of Hunan Province under Grant Nos. 05C756 and 06C766, National Natural Science Foundation of China under Grant Nos. 10274093 and 10474118, the Foundation for Youth Core-Teachers of Hunan Province under Grant No. 2003165, and the Science Research Fund of Hunan Institute of Humanity and Science and Technology under Grant No. 2005A001.We would like to thank Dr. Wen-Xing Yang and Xiao-Long Zhang for many helpful discussions.
文摘We propose a scheme for robustly storing multi-atom entangled states involving Bell states, three-particle W-state, n-particle W-like-states, generalized multi-particle W-states, n-particle GHZ-states, and partially entangled states in cavity QED. Our scheme can preserve the internal structure of the entangled states above, with only generation of a global phase corresponding to each of entangled states during the storage of them. One single-mode cavity and n identical two-level atoms are required. Our scheme may be realized in the present technology. The idea may be also utilized to store multi-trapped-ion entangled states in linear ion trap.
文摘Using bi-spinor fields we write the pseudo-scalar and bi-spinor fields that are characterized by the field functions of coordinates of several particles, namely multi-particle fields. By applying the quantization procedure to these multi-particle fields, hadronic creation and annihilation operators have been obtained.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12205006 and 11975025)the Excellent Youth Scientific Research Project of Anhui Province(Grant No.2022AH030107)+1 种基金the Natural Science Foundation of Anhui Higher Education Institutions of China(Grant No.KJ2020A0504)the International Joint Research Center of Simulation and Control for Population Ecology of Yangtze River in Anhui(Grant No.12011530158).
文摘Turing patterns are typical spatiotemporal ordered structures in various systems driven far from thermodynamic equilibrium.Turing’s reaction-diffusion theory,containing a long-range inhibiting agent and a local catalytic agent,has provided an explanation for the formation of some patterns in nature.Numerical,experimental and theoretical studies about Turing/Turing-like patterns have been generally focused on systems driven far from thermodynamic equilibrium.The local dynamics of these systems are commonly very complex,which brings great difficulties to understanding of formation of patterns.Here,we investigate a type of Turing-like patterns in a near-equilibrium thermodynamic system experimentally and theoretically,and put forward a new formation mechanism and a quantitative method for Turing/Turing-like patterns.Specifically,we observe a type of Turing-like patterns in starch solutions,and study the effect of concentration on the structure of patterns.The experimental results show that,with the increase of concentration,patterns change from spots to inverse spots,and labyrinthine stripe patterns appear in the region of intermediate concentration.We analyze and model the formation mechanism of these patterns observed in experiments,and the simulation results agree with the experimental results.Our conclusion indicates that the random aggregation of spatial components leads to formation of these patterns,and the proportion of spatial components determines the structures.Our findings shed light on the formation mechanism for Turing/Turing-like patterns.
基金Supported by the National Natural Science Foundation of China (No.60704017)
文摘In most probabilistic teleportation schemes, if the teleportation fails, the unknown quantum state will be completely ruined. In addition, the frequently proposed high-dimensional unitary operations are very difficult to realize experimentally. To maintain the integrity of the unknown quantum state to be teleported, this analysis does not focus attention on the original multi-particle state but seeks to construct a faithful channel with an ancillary particle and a unified high-dimensional unitary operation. The result shows that if the construction of the multi-group Einstein-Podolsky-Rosen pair succeeds, the original multi-particle state can be used to deterministically teleport the unknown quantum state of the entangled multiple particles which avoids undermining the integrity of the unknown state brought about by failure. This unified high-dimensional operation is appealing due to the obvious experimental convenience.
文摘For measurement of sediment spatial concentration of nearshore seawater, a turbid water system with several. kinds of particles is investigated from the viewpoint of the characteristics of particles. Firstly, the classical physical and chemical conductivity formula is extended to macro-particle (such as sand) conductivity formula. Secondly, the Fricke formula suitable for only one kind of particles is extended to the conductivity formula suitable for several kinds of particles.. Finally, the multi-particle conductivity formula is applied to the measurement of sediment spatial concentration.
基金support by Shandong Province National Natural Science Foundation of China(No.ZR2023QE036).
文摘Lithium-ion batteries have been rapidly developed as clean energy sources in many industrial fields,such as new energy vehicles and energy storage.The core issues hindering their further promotion and application are reliability and safety.A digital twin model that maps onto the physical entity of the battery with high simulation accuracy helps to monitor internal states and improve battery safety.This work focuses on developing a digital twin model via a mechanism-data-driven parameter updating algorithm to increase the simulation accuracy of the internal and external characteristics of the full-time domain battery under complex working conditions.An electrochemical model is first developed with the consideration of how electrode particle size impacts battery characteristics.By adding the descriptions of temperature distribution and particle-level stress,a multi-particle size electrochemical-thermal-mechanical coupling model is established.Then,considering the different electrical and thermal effect among individual cells,a model for the battery pack is constructed.A digital twin model construction method is finally developed and verified with battery operating data.
文摘There exist interactions among pedestrians and between pedestrian and environment in evacuation. These interactions include attraction, repulsion and friction that play key roles in human evacuation behaviors, speed and efficiency. Most former evacuation models focus on the attraction force, while repulsion and friction are not well modeled. As a kind of multi-particle self-driven model, the social force model introduced in recent years can represent those three forces but with low simulation efficiency because it is a continuous model with complex rules. Discrete models such as the cellular automata model and the lattice gas model have simple rules and high simulation efficiency, but are not quite suitable for interactions’ simulation. In this paper, a new cellular automata model based on traditional models is introduced in which repulsion and friction are modeled quantitatively. It is indicated that the model can simulate some basic behaviors, e.g. arching and the “faster-is-slower” phenomenon, in evacuation as multi-particle self-driven models, but with high efficiency as the normal cellular automata model and the lattice gas model.
基金supported by the China National Key Research and Development Plan Project (Grant No.2018YFA0702300)the National Natural Science Foundation of China (Grant No.51676061)the Taishan Scholars of Shandong Proviance (Grant No.tsqn201812105)。
文摘Radiative cooling can achieve cooling effect without consuming any energy by delivering energy into outer space(3K) through"atmospheric window"(8–13 μm). Conventional radiative cooling coating with multi-layer structure was severely restricted during application due to its complex preparation process and high cost. In this study, a single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles was proposed. The algorithm for calculating the radiative properties of the multi-particle system was developed. Monte Carlo ray-tracing method combined with that algorithm was used to solve the radiative transfer equation(RTE) of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles.The effects of particle diameter, volume fraction and coating thickness on radiative cooling performance were analyzed to obtain the best radiative cooling performance. The numerical results indicated that the average reflectivity of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles in the solar spectrum can reach 95.6%, while and the average emissivity in the "atmospheric window" spectrum can reach 94.9% without additional silver-reflectance layer. The average reflectivity in the solar spectrum and average emissivity in the "atmospheric window" spectrum of the single-layer radiative cooling coating with mixture of TiO_(2) particles and SiO_(2) particles can increase 4.6% and 4.8% compared to the double-layer radiative cooling coating. This numerical research results can provide a theoretical guidance for design and optimization of single-layer radiative cooling coatings containing mixed nanoparticles.
基金Supported by the National Natural Science Foundation of China(No. 60704017)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No. 09KJD120003)
文摘Teleportation schemes based on probabilistic channels usually rely heavily on the implementation of high-dimensional unitary operations. Since high-dimensional unitary operations are very difficult to directly implement in physics experiments, methods are used to avoid high-dimensional unitary operations during the teleportation process. This paper describes how to construct a deterministic teleportation channel and a control channel using Bell state measurements only instead of high-dimensional unitary operations. Here, the general four-particle and five-particle class states are used as the potential quantum channel and the control channel for deterministic teleportation even without access to the relevant parameters. The results show that this scheme makes physical realization of teleportation more reasonable.
基金Supported by the National Natural Science Foundation of China (11775098,U1867210,11405072)Jilin Scientific and Technological Development Programs(20190201137JC,20180520195JH)+4 种基金the 13th Five-Year Plan of Scientific Research of Jilin Province (JJKH20180117KJ)China Postdoctoral Science Foundation(2015M571354,2013M541285)the National Basic Research Programme of China (2007CB815005)the Fundamental Research Funds for the Central Universitiesthe Graduate Innovation Fund of Jilin University。
文摘The level structures of 93 Mo are investigated using Large Scale Shell Model calculations,and reasonable agreement is obtained between the experimental and calculated values.The calculated results show that the lower-lying states are mainly dominated by proton excitations from the If5/2,2 p3/2,and 2 p1/2 orbitals into the higher orbitals across the Z=38 or Z=40 subshell closure.For the higher-spin states,multi-particle excitations,including the excitation of 2 d5/2 neutrons across the N=56 subshell closure into the high-j intruder 1 h11/2 orbital,are essential.Moreover,the previously unknown spin-parity assignments of the six higher excited states in 93 Mo are inferred from the shell model calculations.
基金Supported by NSFC (91126003)the State Key Development Program of Basic Research of China (2007CB209904)
文摘Space-charge forces acting in mismatched beams have been identified as a major cause of beam halo. In this paper,we describe the beam halo experimental results in a FODO beam line at IHEP. With this beam transport line, experiments are carried out to compare the measured data with the multi-particle simulations and to study the formation of a beam halo. The maximum measured amplitudes of the matched and mismatched beam profiles agree well with simulations. Details of the experiment are presented.
基金Supported by the National Natural Science Foundation of China (12135013,11975242)supported in part by National Key Research and Development Program of China (2020YFA0406400)。
文摘A new approach for tree-level amplitudes with multiple fermion lines is presented.It primarily focuses on the simplification of fermion lines.By calculating two vectors recursively without any matrix multiplications,the result of a fermion line is reduced to a very compact form depending only on the two vectors.Comparisons with other packages are presented,and the results show that our package FDC provides a very good performance in the processes of multiple fermion lines with this new approach and some other improvements.A further comparison with WHIZARD shows that this new approach has a competitive efficiency in computing pure amplitude squares without phase space integration.
基金Supported by National Natural Science Foundation of China(11405237,11504388)
文摘Laser cooling of Li-like C^3+and O^4+relativistic heavy ion beams is planned at the experimental Cooler Storage Ring(CSRe). Recently, a preparatory experiment to test important prerequisites for laser cooling of relativistic^12C^3+ion beams using a pulsed laser system has been performed at the CSRe. Unfortunately, the interaction between the ions and the pulsed laser cannot be detected. In order to study the laser cooling process and find the optimized parameters for future laser cooling experiments, a multi-particle tracking method has been developed to simulate the detailed longitudinal dynamics of laser-cooled ion beams at the CSRe. Simulations of laser cooling of the^12C^3+ion beams by scanning the frequency of the RF-buncher or continuous wave(CW) laser wavelength have been performed. The simulation results indicate that ion beams with a large momentum spread could be laser-cooled by the combination of only one CW laser and the RF-buncher, and show the requirements of a successful laser cooling experiment. The optimized parameters for scanning the RF-buncher frequency or laser frequency have been obtained.Furthermore, the heating effects have been estimated for laser cooling at the CSRe. The Schottky noise spectra of longitudinally modulated and laser-cooled ion beams have been simulated to fully explain and anticipate the experimental results. The combination of Schottky spectra from the highly sensitive resonant Schottky pick-up and the simulation methods developed in this paper will be helpful to investigate the longitudinal dynamics of RF-bunched and ultra-cold ion beams in the upcoming laser cooling experiments at the CSRe.