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Gedanken Experiment for Refining the Unruh Metric Tensor Uncertainty Principle via Schwarzschild Geometry and Planckian Space-Time with Initial Nonzero Entropy and Applying the Riemannian-Penrose Inequality and Initial Kinetic Energy for a Lower Bound to Graviton Mass (Massive Gravity) 被引量:36
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第1期106-124,共19页
This paper is with the permission of Stepan Moskaliuk similar to what he will put in the confer-ence proceedings of the summer teaching school and workshop for Ukrainian PhD physics stu-dents as given in Bratislava, a... This paper is with the permission of Stepan Moskaliuk similar to what he will put in the confer-ence proceedings of the summer teaching school and workshop for Ukrainian PhD physics stu-dents as given in Bratislava, as of summer 2015. With his permission, this paper will be in part reproduced here for this journal. First of all, we restate a proof of a highly localized special case of a metric tensor uncertainty principle first written up by Unruh. Unruh did not use the Roberson-Walker geometry which we do, and it so happens that the dominant metric tensor we will be examining, is variation in δg<sub>tt</sub>. The metric tensor variations given by δg<sub>rr</sub>, and are negligible, as compared to the variation δg<sub>tt</sub>. Afterwards, what is referred to by Barbour as emergent duration of time is from the Heisenberg Uncertainty principle (HUP) applied to δg<sub>tt </sub>in such a way as to give, in the Planckian space-time regime a nonzero minimum non zero lower ground to a massive graviton, m<sub>graviton</sub>. The lower bound to the massive graviton is influenced by δg<sub>tt </sub>and kinetic energy which is in the Planckian emergent duration of time δt as (E-V) . We find from δg<sub>tt </sub>version of the Heisenberg Uncertainty Principle (HUP), that the quantum value of the Δt·ΔE Heisenberg Uncertainty Principle (HUP) is likely not recoverable due to δg<sub>tt </sub>≠ Ο(1)~g<sub>tt</sub> ≡ 1. i.e. δg<sub>tt</sub>≠ Ο(1) . i.e. is consistent with non-curved space, so Δt · ΔE ≥ no longer holds. This even if we take the stress energy tensor approximation T<sub>ii</sub>= diag (ρ ,-p,-p,-p) where the fluid approximation is used. Our treatment of the inflaton is via Handley et al., where we consider the lower mass limits of the graviton as due to when the inflaton is many times larger than a Potential energy, with a kinetic energy (KE) proportional to ρ<sub>w</sub> ∝ a<sup>-3(1-w)</sup> ~ g*T<sup>4</sup> , with g* initial degrees of freedom, and T initial temperature. Leading t 展开更多
关键词 Massive Gravitons heisenberg Uncertainty Principle (HUP) Riemannian-Penrose Inequality
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量子位Heisenberg XX开链中边界量子位之间的纠缠 被引量:13
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作者 惠小强 陈文学 +1 位作者 刘起 岳瑞宏 《物理学报》 SCIE EI CAS CSCD 北大核心 2006年第6期3026-3031,共6页
Heisenberg开链对研究量子态在自旋链上的传递有重要的意义.本文研究了五量子位Heisenberg XX开链中边界量子位之间的纠缠,在该系统中引入了磁杂质和系统杂质且它们之间满足线性关系时,该系统可以精确求解,此时边界量子位之间存在纠缠.... Heisenberg开链对研究量子态在自旋链上的传递有重要的意义.本文研究了五量子位Heisenberg XX开链中边界量子位之间的纠缠,在该系统中引入了磁杂质和系统杂质且它们之间满足线性关系时,该系统可以精确求解,此时边界量子位之间存在纠缠.选择合适的杂质参数和磁场参数,该边界纠缠的最大值可达到0·5· 展开更多
关键词 heisenberg XX开链 边界纠缠 杂质
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三量子位Heisenberg XX链中杂质对纠缠的影响 被引量:8
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作者 张涛 惠小强 岳瑞宏 《物理学报》 SCIE EI CAS CSCD 北大核心 2004年第8期2755-2760,共6页
研究了有杂质时三量子位HeisenbergXX链中正常格点之间的热纠缠情况 ,给出了Concurrence的解析表达式 .进一步的讨论发现 ,杂质对正常格点的热纠缠有着重要的影响 ,甚至能够改变纠缠在反铁磁区的特性 .理论表明 。
关键词 heisenberg XX链 杂质格点 热纠缠 量子信息论 量子态纠缠 Concurrence计算
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n-李代数的中心扩张 被引量:8
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作者 白瑞蒲 张艳艳 孟道骥 《数学年刊(A辑)》 CSCD 北大核心 2006年第4期491-502,共12页
对n-李代数的中心扩张问题进行了研究,提出了Heisenberg n-李代数的概念,并对任意一个线性空间V,给出了构造Heisenberg n-李代数H(V)的一种方法且研究了一类特殊类型Heisenberberg n-李代数的导子代数的结构.
关键词 N-李代数 中心扩张 heisenberg N-李代数
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Best Constants for Moser-Trudinger Inequalities,Fundamental Solutions and One-Parameter Representation Formulas on Groups of Heisenberg Type 被引量:8
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作者 COHN William S. 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第2期375-390,共16页
We derive the explicit fundamental solutions for a class of degenerate(or singular)one- parameter subelliptic differential operators on groups of Heisenberg(H)type.This extends the result of Kaplan for the sub-Laplaci... We derive the explicit fundamental solutions for a class of degenerate(or singular)one- parameter subelliptic differential operators on groups of Heisenberg(H)type.This extends the result of Kaplan for the sub-Laplacian on H-type groups,which in turn generalizes Folland's result on the Heisenberg group.As an application,we obtain a one-parameter representation formula for Sobolev functions of compact support on H-type groups.By choosing the parameter equal to the homogeneous dimension Q and using the Mose-Trudinger inequality for the convolutional type operator on stratified groups obtained in[18].we get the following theorem which gives the best constant for the Moser- Trudiuger inequality for Sobolev functions on H-type groups. Let G be any group of Heisenberg type whose Lie algebra is generated by m left invariant vector fields and with a q-dimensional center.Let Q=m+2q.Q'=Q-1/Q and Then. with A_Q as the sharp constant,where ▽G denotes the subelliptic gradient on G. This continues the research originated in our earlier study of the best constants in Moser-Trudinger inequalities and fundamental solutions for one-parameter subelliptic operators on the Heisenberg group [18]. 展开更多
关键词 heisenberg group Groups of heisenberg type Sobolev inequalities Moser-Trudinger inequalities Best constants One-Parameter representation formulas Fundamental solutions
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Heisenberg Group and Energy-Momentum Conservative Law in de-Sitter Spaces—— In Memory of the 100th Anniversary of Einstein's Special Relativity and the 70th Anniversary of Dirac's de-Sitter Spaces 被引量:9
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作者 LU Qi-Keng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期389-392,共4页
In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group ther... In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group there is a subgroup group isomorphic to the Heisenberg group and the generators of this groups are the energy-momentum operators which obey a conservative law. 展开更多
关键词 energy-momentum conservation heisenberg grup de-Sitter space
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A Note on Hermite and Subelliptic Operators 被引量:7
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作者 Der Chen CHANG Jing Zhi TIE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第4期803-818,共16页
In this note, we compute the fundamental solution for the Hermite operator with singularity at an arbitrary point y∈R^n. We also apply this result to obtain the fundamental solutions for the Grushin operator in R^2 a... In this note, we compute the fundamental solution for the Hermite operator with singularity at an arbitrary point y∈R^n. We also apply this result to obtain the fundamental solutions for the Grushin operator in R^2 and the sub-Laplacian in the Heisenberg group Hn. 展开更多
关键词 Hermite operator heisenberg group SUB-LAPLACIAN Gruhsin operator Heat kernel Laguerre function
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Heisenberg algebra for noncommutative Landau problem 被引量:7
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作者 李康 曹小华 汪东燕 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2236-2239,共4页
The Landau problem on non-commutative quantum mechanics is studied, where the Heisenberg algebra and the Landau energy levels as well as the non-commutative angular momentum are constructed in detail in non-commutativ... The Landau problem on non-commutative quantum mechanics is studied, where the Heisenberg algebra and the Landau energy levels as well as the non-commutative angular momentum are constructed in detail in non-commutative space and non-commutative phase space respectively. 展开更多
关键词 non-commutative quantum mechanics Landau problem heisenberg algebra
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Local Schrodinger flow into Kahler manifolds 被引量:7
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作者 丁伟岳 王友德 《Science China Mathematics》 SCIE 2001年第11期1446-1464,共19页
In this paper we show that there exists a unique local smooth solution for the Cauchy problem of the Schrodinger flow for maps from a compact Riemannian manifold into a complete Kahler manifold, or from a Euclidean sp... In this paper we show that there exists a unique local smooth solution for the Cauchy problem of the Schrodinger flow for maps from a compact Riemannian manifold into a complete Kahler manifold, or from a Euclidean space Rm into a compact Kahler manifold. As a consequence, we prove that Heisenberg spin system is locally well-posed in the appropriate Sobolev spaces. 展开更多
关键词 Schriidinger flow heisenberg spin system local existence Kahler manifold.
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Affine Connections and Gauss-Bonnet Theorems in the Heisenberg Group
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作者 WANG Yong 《数学进展》 CSCD 北大核心 2024年第5期1103-1119,共17页
In this paper,we compute sub-Riemannian limits of Gaussian curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for a Euclidean C2-smooth surface in the Heisenberg gro... In this paper,we compute sub-Riemannian limits of Gaussian curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for a Euclidean C2-smooth surface in the Heisenberg group away from characteristic points and signed geodesic curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for Euclidean C2-smooth curves on surfaces.We get Gauss-Bonnet theorems associated to two kinds of Schouten-Van Kampen affine connections in the Heisenberg group. 展开更多
关键词 Schouten-Van Kampen affine connection the adapted connection Gauss-Bonnet theorem sub-Riemannian limit heisenberg group
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Definite Answer for Riemann Hypothesis Zeta 3/2 Function Provided by New Material Yb2Si2O7 in Quantum Mechanics
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Modern Physics》 2024年第9期1409-1429,共21页
This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappin... This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappings, and laser photons governed by electromagnetically induced transparency (EIT) to examine the existence of the RH. In considering the well-developed as Riemann zeta function, we find that the existence of RH has a corrected and self-consistent solution. Specifically, there is the only one pole at s = 1 on the complex plane for Riemann’s functions, which generalizes to all non-trivial zeros while s > 1. The essential solution is based on the BEC phases and on the nature of the laser photon(s). This work also incorporates Heisenberg commutators [ x^,p^]=1/2in the field of quantum mechanics. We found that a satisfactory solution for the RH would be incomplete without the formalism of Heisenberg commutators, BEC phases, and EIT effects. Ultimately, we propose the application of qubits in connection with the RH. 展开更多
关键词 BEC Phases EIT heisenberg Commutators Laser Photons QUBITS Riemann Hypothesis
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Littlewood Paley g-function on the Heisenberg Group 被引量:6
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作者 He Ping LIU Rui Qin MA 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第1期95-100,共6页
We consider the g-function related to a class of radial functions which gives a characterization of the L^p-norm of a function on the Heisenberg group.
关键词 heisenberg group G-FUNCTION
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Besov Estimates for Sub-Elliptic Equations in the Heisenberg Group
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作者 Huimin Cheng Feng Zhou 《Advances in Pure Mathematics》 2024年第9期744-758,共15页
In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Be... In this article, we deal with weak solutions to non-degenerate sub-elliptic equations in the Heisenberg group, and study the regularities of solutions. We establish horizontal Calderón-Zygmund type estimate in Besov spaces with more general assumptions on coefficients for both homogeneous equations and non-homogeneous equations. This study of regularity estimates expands the Calderón-Zygmund theory in the Heisenberg group. 展开更多
关键词 heisenberg Group Sub-Elliptic Equations REGULARITY Besov Spaces
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Exploring the Implications of the Deformation Parameter and Minimal Length in the Generalized Uncertainty Principle
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作者 Mahgoub A. Salih Taysir M. Elmahdi 《Journal of Quantum Information Science》 CAS 2024年第1期1-14,共14页
The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are ... The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are approximately equal to the Planck length. In this context, we have introduced a model that utilizes a combination of Schwarzschild’s radius and Compton length to quantify the gravitational length of an object. This model has provided a novel perspective in generalizing the uncertainty principle. Furthermore, it has elucidated the significance of the deforming linear parameter β and its range of variation from unity to its maximum value. 展开更多
关键词 Generalized Uncertainty Principle Deformed heisenberg Algebra Minimal Length
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Entanglement in spin-1 Heisenberg XY chain 被引量:6
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作者 QIN Meng TAO YingJuan +1 位作者 HU MingLiang TIAN DongPing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第7期817-822,共6页
We investigated the quantum entanglement in spin-1 Heisenberg XY chain for two-spin-qutrit and multi-particle systems. As a measure of the entanglement, the negativity of this state was analyzed as a function of the t... We investigated the quantum entanglement in spin-1 Heisenberg XY chain for two-spin-qutrit and multi-particle systems. As a measure of the entanglement, the negativity of this state was analyzed as a function of the temperature and the magnetic field. We gave some numerical results and discussed them in detail. We found that the negativity increases monotonously with the coupling constants |J1| and |J2|, and it showed a symmetry with respect to the point of J1=0 and J2=0. In addition to the above features, there is evidence that the critical temperature is independent of the length of the chain. 展开更多
关键词 heisenberg CHAIN BIPARTITE ENTANGLEMENT NEGATIVITY
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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation
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作者 Vernon Cooray Gerald Cooray +1 位作者 Marcos Rubinstein Farhad Rachidi 《Journal of Electromagnetic Analysis and Applications》 2024年第1期1-9,共9页
In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according ... In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation. 展开更多
关键词 Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy PHOTON heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius
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一类带有奇异项和临界增长的Schrödinger-Possion次椭圆方程正解的存在性
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作者 朱怡颖 索洪敏 +1 位作者 安育成 张鹏 《遵义师范学院学报》 2024年第1期91-98,共8页
本文研究了在Heisenberg群上具有奇异和临界增长的Schrödinger-Possion系统,利用Brézis-Lieb和Brézis-Nirenberg引理,得到了正解的存在性和多重性.
关键词 Schrödinger-Poisson系统 变分方法 扰动方法 heisenberg
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Investigation of soliton solutions with different wave structures to the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation 被引量:5
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作者 M S Osman K U Tariq +4 位作者 Ahmet Bekir A Elmoasry Nasser S Elazab M Younis Mahmoud Abdel-Aty 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第3期7-13,共7页
The principal objective of this article is to construct new and further exact soliton solutions of the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation which investigates the nonlinear dynamics of magnets... The principal objective of this article is to construct new and further exact soliton solutions of the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation which investigates the nonlinear dynamics of magnets and explains their ordering in ferromagnetic materials.These solutions are exerted via the new extended FAN sub-equation method.We successfully obtain dark,bright,combined bright-dark,combined dark-singular,periodic,periodic singular,and elliptic wave solutions to this equation which are interesting classes of nonlinear excitation presenting spin dynamics in classical and semi-classical continuum Heisenberg systems.3D figures are illustrated under an appropriate selection of parameters.The applied technique is suitable to be used in gaining the exact solutions of most nonlinear partial/fractional differential equations which appear in complex phenomena. 展开更多
关键词 SOLITON solutions heisenberg FERROMAGNETIC EQUATION FAN sub-equation method
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Effects of impurity on the entanglement of the three-qubit Heisenberg XXX spin chain 被引量:5
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作者 HU MingLiang1 & TIAN DongPing2 1 School of Science,Xi’an Jiaotong University,Xi’an 710049,China 2 Xi’an Institute of Posts and Telecommunications,Xi’an 710061,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第2期208-214,共7页
We investigate the entanglement of the three-qubit Heisenberg XXX chain in the presence of impurity and obtain the analytical expressions of the concurrence C. It is found that for impurity entanglement, C appears onl... We investigate the entanglement of the three-qubit Heisenberg XXX chain in the presence of impurity and obtain the analytical expressions of the concurrence C. It is found that for impurity entanglement, C appears only when J 1 > J for J > 0, and J 1 > 0 for J < 0, and in these two regions C increases with the increase of J 1, so is the critical temperature T c. When J 1 ? | J |, C reaches its maximum value 0.5 and T c reaches the asymptotic value T c = 3.41448J 1. For entanglement between the normal lattices, C appears only when J > 0 and ?2J < J 1 < J, and initially increases with the increase of J 1 and arrives at the maximum value C max = (e4J/T ?3)/(e4J/T + 3) before it decays to zero gradually, so is the critical temperature T c with, however, the maximum value T cmax = 4J/In3. 展开更多
关键词 heisenberg XXX chain IMPURITY thermal ENTANGLEMENT
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Entanglement in an anisotropic spin-1 Heisenberg chain 被引量:5
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作者 朱燕 朱士群 郝翔 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2229-2236,共8页
The entanglement in an anisotropic spin-1 Heisenberg chain with a uniform magnetic field is investigated. The ground-state entanglement will undergo two different kinds of transitions when the anisotropy △ and the am... The entanglement in an anisotropic spin-1 Heisenberg chain with a uniform magnetic field is investigated. The ground-state entanglement will undergo two different kinds of transitions when the anisotropy △ and the amplitude of the magnetic field B are varied. The thermal entanglement of the nearest neighbour always declines when B increases no matter what the value of the anisotropy is. It is very interesting to note that the entanglement of the next-nearest neighbour can increase to a maximum at a certain magnetic field. Regardless of the boundary condition, the nearestneighbour entanglement always decreases and approaches to a constant value when the size of the system is very large. The constant value of open boundary condition is much larger than that of periodic boundary condition. 展开更多
关键词 ENTANGLEMENT heisenberg chain open boundary condition periodic boundary condition
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