共查询到20条相似文献,搜索用时 78 毫秒
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利用具有量子群对称性的q变形量子谐振子Fock态│n>q生成q变形量子谐振子的Glauber相干态(q-Glauber相干态│a>q)。还讨论了q-Glauber相干态│a>q的完备性、粒子数分布、振子强度分布和最小测不准关系,指出q-Glauber相干态│a>q的相干程度可以用q参数来描述。 相似文献
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q变形叠加态及其特性 总被引:1,自引:0,他引:1
利用q-振子代数提出了一种由q变形振子的本征态(q变形光子数态)叠回由成的态。给出了这种q有叠加态的定义,研究了它们的量子统计性质。也讨论了这种态的压缩和q压缩,并进一步研究了它们的寻常高阶压缩和q高阶压缩。q变形振子是一种非线性振子,通过这些讨论,推广通常的叠加态。 相似文献
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文章给出了q变形的奇偶相干迭加态的表达式,并研究了相应的q变形奇偶相干迭加态光场的N阶压缩效应。 相似文献
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q变形对相干态的相位概率分布特性 总被引:2,自引:0,他引:2
通过推广Pegg和Barnett的相位算符和相位态到q变形的双模情况, 应用数值计算
研究了q变形对相干态的相位概率分布特性. 结果表明, q变形对相干态的相位概率分布受到相位参数、q参数和参数│ξ│的调节, 从而反映出不同的量子相干特性. 相似文献
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叠加q相干态的振幅M次方压缩 总被引:1,自引:1,他引:0
本文构造了以奇偶q相干态为特例的一般叠加q相干态|α,θ〉q=c(|α〉q+e^iθ|-α〉a),并研究了它的振幅M次方压缩性质,发现这种叠加态只存在振幅奇数次方压缩效应。并数值计算了叠加系娄籴形参数对压缩的影响。 相似文献
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相位差与q变形广义相干叠加态的压缩特性 总被引:1,自引:0,他引:1
对于q变形的非简谐振子广义相干态的叠加态β〉+eiφβeiδ〉,其量子涨落的可能高阶压缩阶数可以表示为k≠2πn/δ,这里n是整数.当δ=π时,压缩阶数不能是偶数即只能是奇数,这正是q变形非简谐振子广义奇偶相干态的结果.由此表明参数相位差δ对决定q变形的非简谐振子广义相干态叠加态的高阶压缩阶数起决定性作用. 相似文献
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Tomáš Tyc Brett Hamilton Barry C. Sanders William D. Oliver 《Foundations of Physics》2007,37(11):1519-1539
Whereas boson coherent states with complex parametrization provide an elegant, and intuitive representation, there is no counterpart
for fermions using complex parametrization. However, a complex parametrization provides a valuable way to describe amplitude
and phase of a coherent beam. Thus we pose the question of whether a fermionic beam can be described, even approximately,
by a complex-parametrized coherent state and define, in a natural way, approximate complex-parametrized fermion coherent states.
Then we identify four appealing properties of boson coherent states (eigenstate of annihilation operator, displaced vacuum
state, preservation of product states under linear coupling, and factorization of correlators) and show that these approximate
complex fermion coherent states fail all four criteria. The inapplicability of complex parametrization supports the use of
Grassman algebras as an appropriate alternative.
相似文献
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Tomáš Tyc Brett Hamilton Barry C. Sanders William D. Oliver 《Foundations of Physics》2007,37(7):1027-1048
Whereas boson coherent states with complex parametrization provide an elegant, and intuitive representation, there is no counterpart
for fermions using complex parametrization. However, a complex parametrization provides a valuable way to describe amplitude
and phase of a coherent beam. Thus we pose the question of whether a fermionic beam can be described, even approximately,
by a complex-parametrized coherent state and define, in a natural way, approximate complex-parametrized fermion coherent states.
Then we identify four appealing properties of boson coherent states (eigenstate of annihilation operator, displaced vacuum
state, preservation of product states under linear coupling, and factorization of correlators) and show that these approximate
complex fermion coherent states fail all four criteria. The inapplicability of complex parametrization supports the use of
Grassman algebras as an appropriate alternative.
相似文献
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LIN Ji GAO Xian-Long WANG Ke-Lin 《理论物理通讯》2007,47(1):161-166
We present a comparative study of the ground state of the one-dimensional Hubbard model. We first use a new fermion coherent state method in the framework of Fermi liquid theory by introducing a hole operator and considering the interactions of two pairs electrons and holes. We construct the ground state of the Hubbard model as |〉=[f+∑^tφk1σ1hk2σ2ck3σ3hk4σ4 ∏exp(ρck1σ1 hk2σ2)]|〉0,where φ and ρ are the coupling constants. Our results are then compared to those of varlational methods, density functional theory based on the exact solvable Bethe ansatz solutions, variational Monto-Carlo method (VMC) as well as to the exact result of the infinite system. We find satisfactory agreement between the fermion coherent state scheme and the VMC data, and provide a new picture to deal with the strongly correlated system. 相似文献
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We show that the completeness relation of the charged coherent state can be obtained by using the Mellin transformation and contour integration method. As a result, a modification of the completeness relation of the charged coherent state given by D. Bhaumik et al. (J. Phys. A: Math. Gen. 9 (1976) 1507) is presented. 相似文献
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Using the MelJin inversion formulas we derive the weight function for constructing the completeness relation of the boson SU(3) charged and hypercharged coherent state. A suitable contour integration is selected for this derivation. 相似文献
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Choosing I-concurrence as the measure of bipartite entanglement and using yon Neumann projective local measurements, localizable entanglement (LE) in a three-qutrit system is studied. A superposition of the qutrit-coherent- state of this system is considered ant its LE is obtained and analyzed as a function of the relevant parameters. It is observed that one may achieve the maximal entanglement or no entanglement at all, depending on the choice of the parameters involved. 相似文献
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在顶色辅助的人工色模型下计算了高能e+e-对撞机上top介子辅助的b夸克对产生过程e+e-→bbπ0t的产生截面.发现在一定的参数范围内,这个过程的产生截面大于10fb,比标准模型下标量Higgs粒子辅助的b夸克对产生过程大许多,与最小超对称模型下标量和赝标量Higgs粒子h0,H0,A0的相应产生截面大致相当.人工色理论的信息可能在下一代正负电子对撞实验中探测到. 相似文献
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A scheme is proposed to generate arbitrary, discrete
superpostions of squeezed coherent states of the squeezed center of mass of
$N$ trapped ions along a straight line in phase space.
The scheme is based on a
resonant bichromatic excitation of each trapped ion that generates
displacement and squeezing in the vibrational motion conditioned to each
internal state. In this paper, we also show that such a method can be
used for the engineering of motional quantum states. 相似文献
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QIN Jia-Qian KUANG Ye SHU Xiao-Qin 《理论物理通讯》2007,48(5):908-912
A powerful approach to generate multilevel superposition state in A-type manifold of levels is proposed. In the analysis, we introduce a group of rotations to transform the coupled system to a simpler form, which involves one coupled and several decoupled, dark states in the ground state manifold. Then an arbitrary superposition state of initial and final states can be created. In particular, when the Rabi frequencies of the Stokes pulses have equal magnitudes, a superposition state (equal population of the (n - 2) superposition states) will be generated. A numerical simulation of coherence generation is given. It is shown that a small transient population in metastable state decreases as the intensity of Stokes pulses increases. Experimental implementation in Neon atom is given. 相似文献
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ZHENGShi-Biao 《理论物理通讯》2002,37(1):87-90
A method is presented for generating highly squeezed states of a cavity field via the atom-cavity field interaction of the Raman type.In the scheme a sequence of three-level Λ-type atoms interacts with a cavity field,displaced by a classical source,in a Raman manner.Then the atomic states are measured.By this way the cavity field may collapse onto a superposition of several coherent states,which exhibits strong squeezing.The scheme can also be used to prepare superpositions of many two-mode coherent states for two cavity fields.The coherent states in each mode are on a straight line.This is the first way for preparing multi-component entangled coherent states of this type in cavity QED. 相似文献