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具有Fe_4N结构的混自旋最近邻的Ising模型磁性质 被引量:1
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作者 许星光 赵杰 《辽宁石油化工大学学报》 CAS 2009年第3期81-84,共4页
在晶场作用下对具有Fe4N结构的混自旋Ising模型,采用平均场理论,推导出考虑最近邻相互作用下系统的磁矩和自由能的理论公式,重点考察了最近邻格点的相互作用及晶场对系统磁性质的影响,得到了系统的基态相图和有限温度的磁化曲线,观察到... 在晶场作用下对具有Fe4N结构的混自旋Ising模型,采用平均场理论,推导出考虑最近邻相互作用下系统的磁矩和自由能的理论公式,重点考察了最近邻格点的相互作用及晶场对系统磁性质的影响,得到了系统的基态相图和有限温度的磁化曲线,观察到系统的相变特征:重入现象及二级相变。研究发现,二级相变是普遍现象,当DA/|J1|、DB/|J1|取得足够大时,系统一定存在二级相变。基态相图中D1与O1及D2与O1、O2的边界线上会发生重入现象。 展开更多
关键词 平均场理论 混自旋 基态相图 磁化曲线 重入现象
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立方点阵稀磁混自旋模型基态相图 被引量:3
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作者 张翠萍 牟有静 孙宇秋 《辽宁大学学报(自然科学版)》 CAS 2001年第1期52-55,共4页
用相关有效场理论研究立方点阵、稀磁混自旋Ising模型的基态相性质 .计算了基态相变点和基态补偿点随磁原子浓度的变化规律、给出了基态相图 .
关键词 双亚点阵 ISING模型 相图 相关有效场方法 立方点阵 稀磁混自旋 磁性质
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混自旋σ=3/2和S=2与σ=3/2和S=5/2Ising系统基态性质的比较
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作者 缪海凌 魏国柱 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第7期1057-1060,共4页
研究了混自旋σ=3/2和S=2与混自旋σ=3/2和S=5/2两种Ising系统的基态性质.根据能量最低原理,通过比较各种可能基态构型的基态能,确定出了系统的基态相图.并得到了基态能Eg随DA/(zJ)和DB/(zJ)的变化规律.结果表明,对于混自旋σ=3/2和S=2 ... 研究了混自旋σ=3/2和S=2与混自旋σ=3/2和S=5/2两种Ising系统的基态性质.根据能量最低原理,通过比较各种可能基态构型的基态能,确定出了系统的基态相图.并得到了基态能Eg随DA/(zJ)和DB/(zJ)的变化规律.结果表明,对于混自旋σ=3/2和S=2 Ising系统可存在无序相,而对于混自旋σ=3/2和S=5/2 Ising系统只存在有序相.两种系统的基态能均随着DA/(zJ),DB/(zJ)值的变大而线性升高,但不同区域的斜率不同.DA/(zJ),DB/(zJ)值越大,基态能升高得越慢.此外发现对于混自旋σ=3/2和S=2 Ising系统存在4种构型共存点(0.5,0.5),而混自旋σ=3/2和S=5/2 Ising系统不存在4种构型共存点. 展开更多
关键词 混自旋 ISING 基态能 基态相图 晶场
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不同单离子各向异性稀磁混自旋Ising模型的亚铁磁性相图
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作者 张翠萍 《中国新技术新产品》 2016年第13期69-70,共2页
本文利用平均场理论对基于Bogoliubov非均匀Gibbs自由能的亚铁磁的交互作用(JAB<0)和不同单离子的各向异性参数的亚铁磁Ising系统进行研究,给出其相图。
关键词 平均场理论 稀磁混自旋Ising模型 相图
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配位数为6的稀磁混自旋Ising系统磁性质理论推导
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作者 张翠萍 金爱华 孙宇秋 《电大理工》 2000年第4期30-31,33,共3页
用相关有效场理论研究并推导出配位数为6时稀磁混自旋Ising系统磁学性质公式。
关键词 混自旋Ising模型 相关有效场 磁原子浓度 配位数
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不同单离子各向异性稀混自旋Ising模型的磁化率
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作者 张翠萍 《科技创新导报》 2016年第8期159-160,共2页
该文利用平均场理论对混自旋为3/2和5/2、结构为BNAypp)(1?的具有亚铁磁的交互作用和不同单离子各向异性参数的亚铁磁Ising系统的磁化率进行研究,找出其不服从居里定律的情况。
关键词 平均场 稀磁混自旋Ising模型 磁化率
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平均场理论下各向异性稀磁混自旋的理论公式
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作者 张翠萍 《辽宁师专学报(自然科学版)》 2016年第2期7-9,共3页
为研究不同单离子各向异性参数的亚铁磁混自旋Ising系统的性质,用平均场理论的方法对结构为(A_pN_(1-p))_yB的亚铁磁体进行研究,导出其交互作用J_(AB)<0时的理论公式,为进一步研究打下基础.
关键词 平均场理论 稀磁混自旋Ising模型 哈密顿量
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具有铁磁性Ising模型的磁性质
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作者 许星光 赵杰 《科学技术与工程》 2010年第13期3036-3040,共5页
以Fe4N为原型,构建在晶场作用下的混自旋Ising模型。利用平均场理论,得到该模型的磁矩和自由能公式;绘制了不同相互作用下的磁化曲线;研究了系统的磁性质。发现系统发生了丰富的相变特性:系统存在一级有序-无序相变、重入现象和二级相变... 以Fe4N为原型,构建在晶场作用下的混自旋Ising模型。利用平均场理论,得到该模型的磁矩和自由能公式;绘制了不同相互作用下的磁化曲线;研究了系统的磁性质。发现系统发生了丰富的相变特性:系统存在一级有序-无序相变、重入现象和二级相变;晶场D_A/|J_1|和D_B/|J_1|对系统的磁性质所起作用相似。随着晶场的增加,一级有序-无序相变的温度升高,重入现象的温度降低;一级有序-无序相变和重入现象的温度间距逐渐缩小,直至这两种相变消失。 展开更多
关键词 混自旋 平均场理论 磁化曲线 一级有序-无序相变
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不同单离子各向异性亚铁磁Ising模型的热力学性质
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作者 张翠萍 《中国新技术新产品》 2016年第14期36-37,共2页
用平均场理论对基于Bogoliubov非均匀Gibbs自由能的交互作用(J_(AB_<0)和不同单离子各向异性参数的亚铁磁Ising系统进行热力学研究,获取其内能、熵、比热与温度的关系。
关键词 平均场理论 稀磁混自旋Ising模型 比热
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Adaptive multicascade attribute reduction based on quantum-inspired mixed co-evolution
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作者 丁卫平 王建东 +1 位作者 施佺 管致锦 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期145-150,共6页
Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multi... Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multicascade attribute reduction algorithm based on quantum-inspired mixed co-evolution is proposed. First, a novel and efficient self- adaptive quantum rotation angle strategy is designed to direct the participating populations to mutual adaptive evolution and to accelerate convergence speed. Then, a multicascade model of cooperative and competitive mixed co-evolution is adopted to decompose the evolutionary attribute species into subpopulations according to their historical performance records, which can increase the diversity of subpopulations and select some elitist individuals so as to strengthen the sharing ability of their searching experience. So the global optimization reduction set can be obtained quickly. The experimental results show that, compared with the existing algorithms, the proposed algorithm can achieve a higher performance for attribute reduction, and it can be considered as a more competitive heuristic algorithm on the efficiency and accuracy of minimum attribute reduction. 展开更多
关键词 attribute reduction mixed co-evolution self- adaptive quantum rotation angle performance experience record elitist competition pool
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Anisotropy and Magnetic Field Effects on Entanglement of a Two-Spin (1/2,1) Mixed-Spin Heisenberg XY Chain 被引量:3
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作者 WANG Fei FU Li-Ping GUO Ke-Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期341-344,共4页
We study the entanglement in anisotropie (1/2,1) mixed-spin Heisenberg XY model under the presence of an external magnetic field at thermal equilibrium. By adjusting the anisotropic parameter and the magnetic field,... We study the entanglement in anisotropie (1/2,1) mixed-spin Heisenberg XY model under the presence of an external magnetic field at thermal equilibrium. By adjusting the anisotropic parameter and the magnetic field, one is able to obtain entanglement at higher temperature. We find the evidence of the quantum phase transition in the model and observe that the quantum phase transition point at low temperature moves toward weak magnetic field with the increase of the anisotropic parameter. 展开更多
关键词 ENTANGLEMENT mixed-spin NEGATIVITY quantum phase transition
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Channel's Concurrence and Quantum Teleportation 被引量:3
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作者 LINGYin-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期55-58,共4页
Concurrence can measure the entanglement property of a system. If the channel is a pure state, positive concurrence state can afford the good performance in the teleportation process. If the channel ia a mixed state, ... Concurrence can measure the entanglement property of a system. If the channel is a pure state, positive concurrence state can afford the good performance in the teleportation process. If the channel ia a mixed state, positive concurrence state cannot assure the good performance in the teleportation. The conditions of the positive concurrence and the quantum teleportation in the Heisenberg spin ring is derived. 展开更多
关键词 CONCURRENCE quantum telportation ENTANGLEMENT mixed state heisenberg spinring
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Critical Properties of Mixed Ising Spin System with Different Trimodal Transverse Fields in the Presence of Single-Ion Anisotropy
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作者 CHEN Qiang YAN Shi-Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1131-1136,共6页
Within the framework of an effective field approximation, the effects of single-ion anisotropy and different trimodal transverse fields of two sublattices on the critical properties of the mixed spin-1/2 and spin-1 Is... Within the framework of an effective field approximation, the effects of single-ion anisotropy and different trimodal transverse fields of two sublattices on the critical properties of the mixed spin-1/2 and spin-1 Ising system are investigated on the simple cubic lattice. A smaller single-lon anisotropy can magnify magnetic ordering phases and a larger one can depress magnetic ordering phase for T-Ω1/2 space at low temperatures, while a smaller single-ion anisotropy can hardly change the value of critical transverse field for T-Ω1 space. On the other hand, influences of two different trimodal transverse fields concentrations on tricritical points and magnetic ordering phases take on some interesting results in T-D space. The main reason comes from the common action of single-ion anisotropy, different transverse fields and two trimodal distributions. 展开更多
关键词 critical property mixed spin system trimodal transverse field single-ion anisotropy
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Magnetic Properties of One-Dimensional Ferromagnetic Mixed-Spin Model within Tyablikov Decoupling Approximation
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作者 陈渊 项颖 宋闯闯 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期747-752,共6页
In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correla... In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correlationfunctions are obtained by using the Tyablikov decoupling approximation.Our results show that the magnetic susceptibilityand correlation length are a monotonically decreasing function of temperature regardless of the mixed spins.It isfound that in the case of S = s, our results of one-dimensional mixed-spin model is reduced to be those of the isotropicferromagnetic Heisenberg chain in the whole temperature region.Our results for the susceptibility are in agreement withthose obtained by other theoretical approaches. 展开更多
关键词 magnetic property Green's function method mixed-spin model Tyablikov decoupling approximation
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Longitudinal-Random-Field Mixed Ising Model with Arbitrary Spins
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作者 梁雅秋 魏国柱 +1 位作者 徐晓娟 宋国利 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期957-962,共6页
The longitudinal-random-fieM mixed Ising model consisting of arbitrary spin values has been studied by the use of an effective field theory with correlations (EFT). The phase diagrams of systems with mixed spins: ... The longitudinal-random-fieM mixed Ising model consisting of arbitrary spin values has been studied by the use of an effective field theory with correlations (EFT). The phase diagrams of systems with mixed spins: σ = 1/2, S = 1; σ = 1/2, S = 3/2 are plotted. Not only the discontinuity at T = 0 K, is found when both longitudinal fields are trimodal distributed, but also the trieritical behavior is observed in these phase diagrams between the bimodal and trimodal distributions of longitudinal fields, which is different from the single-spin one. The appearance of tricritical point is independent of the coordination number and spin values. 展开更多
关键词 mixed Ising model random field phase diagram tricritical point
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Effects of Transverse Field on Internal Energy and Specific Heat of a Molecular-Based Materials
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作者 JIANG Wei YU Gui-Hong ZHANG Fan WANG Wei JIANG Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期965-968,共4页
The molecular-based magnetic materials AFe11 Fe111(C2O4)3 have a honeycomb structure in which FeII (S = 2) and FeIH (S= 5/2) occupy sites alternately. They can be described as mixed spin-2 and spin-5/2 Ising mod... The molecular-based magnetic materials AFe11 Fe111(C2O4)3 have a honeycomb structure in which FeII (S = 2) and FeIH (S= 5/2) occupy sites alternately. They can be described as mixed spin-2 and spin-5/2 Ising model with ferrimagnetic interlayer coupling. The influences of the transverse field on the internal energy and the specific heat of the molecalar-based magnetic system have been studied numerically by using the effective-field theory with self-spin correlations and the differential operator technique. 展开更多
关键词 transverse field molecular-based magnet internal energy specific heat
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Mean-Field Studies of a Mixed Spin-3/2 and Spin-2 and a Mixed Spin-3/2 and Spin-5/2 Ising System with Different Anisotropies
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作者 WEI Guo-Zhu MIAO Hai-Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期756-760,共5页
The magnetic properties of a mixed spin-3/2 and spin-2 and a mixed spin-3/2 and spin-5/2 Ising ferromag- netic system with different anisotropies are studied by means of mean-field theory (MFT). The dependence of th... The magnetic properties of a mixed spin-3/2 and spin-2 and a mixed spin-3/2 and spin-5/2 Ising ferromag- netic system with different anisotropies are studied by means of mean-field theory (MFT). The dependence of the phase diagram on single-ion anisotropy strengths is studied too. In the mixed spin-3/2 and spin-2 Ising model, besides the second-order phase transition, the first order-disorder phase transition and the tricritical line are found. In the mixed spin-3/2 and spin-5/2 Ising model, there is no first-order transition and trieritical line. 展开更多
关键词 mixed spin Ising system mean-field theory phase transition
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Degree of Entanglement and Violation of Bell Inequality by Two-Spin-1/2 States
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作者 K.Berrada Y.Hassouni H.Eleuch 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期679-686,共8页
Bell inequality is violated by the quantum mechanical predictions made from an entangled state of the composite system. In this paper we examine this inequality and entanglement measures in the construction of the coh... Bell inequality is violated by the quantum mechanical predictions made from an entangled state of the composite system. In this paper we examine this inequality and entanglement measures in the construction of the coherent states for two-qubit pure and mixed states, we find a link to some entanglement measures through some new parameters (amplitudes of coherent states). Conditions for maximal entanglement and separability are then established for both pure and mixed states. Finally, we analyze and compare the violation of Bell inequality for a class of mixed states with the degree of entanglement by applying the formalism of Horodecki et al. 展开更多
关键词 Bell inequality quantum entanglement coherent states pure and mixed states
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Explicit Expression of Seniority Particle Operator and Its Properties in Quasi-spin Theory
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作者 ZHANG Bo LU Da-Hai DENG Wei-Zhen CHEN Xiao-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期909-913,共5页
The explicit expression of the seniority particle operator and its properties in the quasi-spin theory of nuclear physics is presented in this paper. The seniority particle operator can be used to construct D-pair in ... The explicit expression of the seniority particle operator and its properties in the quasi-spin theory of nuclear physics is presented in this paper. The seniority particle operator can be used to construct D-pair in the microscopic theory of interacting boson model to avoid the seniority mixing problem. 展开更多
关键词 quasi-spin seniority particle seniority mixing problem
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Suppression of Spiral Waves and Spatiotemporal Chaos Under Local Self-adaptive Coupling Interactions
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作者 MA Jun WU Ning-Jie +1 位作者 YING He-Ping YUAN Li-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期121-126,共6页
In this paper, a close-loop feedback control is imposed locally on the Fitzhugh-Nagumo (FHN) system to suppress the stable spirals and spatiotemporal chaos according to the principle of self-adaptive coupling intera... In this paper, a close-loop feedback control is imposed locally on the Fitzhugh-Nagumo (FHN) system to suppress the stable spirals and spatiotemporal chaos according to the principle of self-adaptive coupling interaction. The simulation results show that an expanding target wave is stimulated by the spiral waves under dynamic control period when a local area. of 5 × 5 grids is controlled, or the spiral tip is driven to the board of the system, It is also found that the spatiotemporal chaos can be suppressed to get a stable homogeneous state within 50 time units as two local grids are controlled mutually. The mechanism of the scheme is briefly discussed. 展开更多
关键词 spiral waves spatiotemporal chaos close-loop feedback Fitzhugh-Nagumo (FHN) equation
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