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1.
This paper assesses the utility of momentum space in the density-based quantification of the steric effect proposed by Liu [J. Chem. Phys. 126, 244103 (2007)], which is based on a new energy partition scheme where the total electronic energy is decomposed into contributions from three independent effects: steric, electrostatic, and the fermionic quantum. The steric energy defined in this way is repulsive, exclusive, and extensive and intrinsically linked to Bader's quantum theory of atoms in molecules. In this work, the plausibility of defining and computing steric energies using momentum densities according to this scheme is confirmed from numerical tests. Moreover, we found that the correlation between the experimental scales of the steric energies and theoretical values computed from momentum densities is even better than the same correlation with theoretical estimations obtained from position densities. 相似文献
2.
Bill Poirier 《Foundations of Physics》2001,31(11):1581-1610
In an earlier article [Found. Phys.
30, 1191 (2000)], a quasiclassical phase space approximation for quantum projection operators was presented, whose accuracy increases in the limit of large basis size (projection subspace dimensionality). In a second paper [J. Chem. Phys.
111, 4869 (1999)], this approximation was used to generate a nearly optimal direct-product basis for representing an arbitrary (Cartesian) quantum Hamiltonian, within a given energy range of interest. From a few reduced-dimensional integrals, the method determines the optimal 1D marginal Hamiltonians, whose eigenstates comprise the direct-product basis. In the present paper, this phase space optimized direct-product basis method is generalized to incorporate non-Cartesian coordinate spaces, composed of radii and angles, that arise in molecular applications. Analytical results are presented for certain standard systems, including rigid rotors, and three-body vibrators. 相似文献
3.
F. Borgonovi G. L. Celardo R. Trasarti-Battistoni 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):27-31
Quantum characteristics of the Topological
Non-connectivity Threshold (TNT),
introduced in
[F. Borgonovi, G.L. Celardo, M. Maianti, E. Pedersoli,
J. Stat. Phys. 116, 516 (2004)],
have been analyzed in the hard quantum regime.
New interesting perspectives in term of the possibility
to study the intriguing quantum-classical transition through
Macroscopic Quantum Tunneling have been addressed. 相似文献
4.
Recently, Choudhury (Int. J. Theor. Phys. 10, 1007 2016), proposed a teleportation protocol of three-qubit state using four-qubit quantum channels.According to their scheme the three-qubit entangled states could be teleported by use of three simultaneous quantum channels of four-qubit cluster states. In this paper,we emphasize that the same three-qubit entangled states can be teleported perfectly by using only one quantum channel of four-qubit cluster states. 相似文献
5.
G. Brida M. Genovese F. Piacentini 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):577-580
Following the theoretical suggestion of [E. Santos, Phys. Lett. A 327, 33 (2004);
E. Santos, Eur. Phys. J. D 42, 501 (2007)], we present experimental results addressed to
test restricted families of local realistic models, but without
relying on the fair sampling assumption. 相似文献
6.
Y. Cao A.-M. Wang X.-S. Ma N.-B. Zhao 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):607-617
Based on controlled order rearrange encryption (CORE) for
quantum key distribution using EPR pairs [Fu.G. Deng, G.L. Long,
Phys. Rev. A 68, 042315 (2003)], we propose generalized controlled order
rearrangement encryption (GCORE) protocols of N qubits and N
qutrits, and concretely display them in cases using 3-qubit,
2-qutrit maximally entangled basis states. We further show that our
protocols will become safer with an increase in dimensions and
number of particles. Moreover, we carry out the security analysis
using quantum covariant cloning machine. Although the applications
of the generalized scheme need to be further studied, GCORE has many
distinct features such as large capacity and high efficiency. 相似文献
7.
Dong Shu-bao Feng Er-yin Huang Wu-ying Cui Zhi-feng 《Czechoslovak Journal of Physics》2005,55(1):27-33
Molecular reaction dynamics of Cl + H2 (D2) has been studied on the latest analytical potential energy surface called BW3 using the Monte Carlo quasi-classical trajectory method. Excitation functions, differential cross sections and angular distributions of HCl and DCl products have been calculated. The excitation functions of the Cl (2P3/2) + n-H2 and Cl(2P3/2) + n-D2 reactions are also studied. The results are compared with those of quasi-classical trajectory [M. Alagia et al.: Phys. Chem. Chem. Phys. 2 (2000); F. J. Aoiz et al.: J. Phys. Chem. 100 (1996)], quantum mechanical (QM) calculations [F. J. Aoiz et al.:J. Chem. Phys. 115 (2001)] and experimental data [S. H. Lee et al.: J. Chem. Phys. 110 (1999); F. Dong et al.: J. Chem. Phys. 115 (2001)]. Discussions are given to some new results. 相似文献
8.
通过介绍六粒子纠缠态的新应用研究,提出了一个二粒子任意态的信息分离方案.在这个方案中,发送者Alice、控制者Charlie和接受者Bob共享一个六粒子纠缠态,发送者先执行两次Bell基测量|然后控制者执行一次Bell基测量|最后接受者根据发送者和控制者的测量结果,对自己拥有的粒子做适当的幺正变换,从而能够重建要发送的二粒子任意态.这个信息分离方案是决定性的,即成功概率为100%.与使用相同的量子信道进行二粒子任意态的信息分离方案相比,本文提出的方案只需要进行Bell基测量而不需要执行多粒子的联合测量,从而使得这个方案更简单、更容易,并且在目前的实验室技术条件下是能够实现的. 相似文献
9.
We propose a novel deterministic protocol that two senders are capable of remotely preparing arbitrary two-and three-qubit states for a remote receiver using EPR pairs and GHZ state as the quantum channel.Compared with the existing deterministic protocols [An et al.2011 Phys.Lett.A 375 3570 and Chen et al.2012 J.Phys.A:Math.Theor.45 055303],the quantum resources and classical information in our scheme are decreased,and the whole operation process is simplified. 相似文献
10.
R. K. Varma 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2012,66(2):39
Matter wave interference effects on the macro-scale predicted by the author in charged particle dynamics in a magnetic field
[R.K. Varma, Phys. Rev. E 64, 036608 (2001)], and observed subsequently [R.K. Varma, A.M. Punithavelu, S.B. Banerjee, Phys. Rev. E 65, 026503 (2002); R.K. Varma, S.B. Banerjee, Phys. Scr. 75, 19 (2007)] have been shown here to be an interesting consequence of quantum entanglement between the parallel and perpendicular
degrees of freedom of the particle. Treating the problem in the framework of the inelastic scattering theory, it is shown
that these macro-scale matter waves are generated in the ‘parallel’ degree of freedom as a modulation of the plane wave state
of the particle along the field concomitantly with the excitation of Landau levels in the perpendicular degree of freedom
in an inelastic scattering episode. We highlight here the role of quantum entanglement leading to the generation of this macro-scale
quantum entity which has been shown to exhibit observable consequences. This case also exemplifies a situation exhibiting
quantum entanglement on the macro-scale. 相似文献
11.
S.M.S. da Costa M.H.F. Bettega 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,3(1):67-71
We report elastic integral, momentum transfer and differential cross sections for electron scattering by N2O for energies up to 50 eV. These results were obtained at the static-exchange approximation with the Schwinger Multichannel
Method with Pseudopotentials [M.H.F. Bettega, L.G. Ferreira and M.A.P. Lima, Phys. Rev. A 47, 1111 (1993)]. In general our results show good agreement with experimental data and with other theoretical results but some
discrepancies are found. We have also found a shape resonance around 4 eV in agreement with previous calculations using the R-matrix Method of Sarpal et al. [J. Phys. B 29, 857 (1996)]. On the other hand, the existence of a resonance at about 13 eV, clearly seen by the Schwinger Variational Iterative Method [Michelin et al., J. Phys. B 29, 2115 (1996)], can not be confirmed by our calculations. At this energy, our cross sections show a broad bump with no clear resonant behavior given by the eigenphase sum.
Received: 13 November 1997 / Revised: 13 March 1998 / Accepted: 9 April 1998 相似文献
12.
G. F. Zhang H. Fan A. L. Ji W. M. Liu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2012,66(2):34
By using geometric measure of discord (GMOD) [B. Dakić, V. Vedral, Č. Brukner, Phys. Rev. Lett. 105, 109502 (2010)] and measurement-induced nonlocality (MIN) [S. Luo, S. Fu, Phys. Rev. Lett. 106, 120401 (2011)], we investigate quantum correlation of a pair of two-level systems, each of which is interacting with a reservoir
at finite temperature T. We show that, for a broad class of states of the system, GMOD and MIN can endure sudden death, and there is no asymptotic
decay for MIN while asymptotic decay exists for GMOD. We also give the dynamics of GMOD and MIN with respect to the temperature
and illustrate their different characteristics. 相似文献
13.
A general scheme is presented for using different numbers of ‘time slices’ for different degrees of freedom in a path integral evaluation of the Boltzmann operator for a large molecular system. This will be particularly useful, for example, in evaluating the ‘quantum instanton’ rate constant [cf. W.H. Miller, Y. Zhao, M. Ceotto, S. Yang. J. Chem. Phys., 119, 1329 (2003)] for H atom transfer reactions, or any applications involving atoms with largely differing masses. 相似文献
14.
J. B. Satinover D. Sornette 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(3):369-384
Human beings like to believe they are in control of their
destiny. This ubiquitous trait seems to increase motivation and persistence,
and is probably evolutionarily adaptive [J.D. Taylor, S.E. Brown, Psych. Bull. 103, 193 (1988); A. Bandura,
Self-efficacy: the exercise of control (WH Freeman, New
York, 1997)]. But how good really is our
ability to control? How successful is our track record in these areas? There
is little understanding of when and under what circumstances we may
over-estimate [E. Langer, J. Pers. Soc. Psych. 7, 185 (1975)] or even lose our ability to control and optimize outcomes,
especially when they are the result of aggregations of individual
optimization processes. Here, we demonstrate analytically using the theory
of Markov Chains and by numerical simulations in two classes of games, the
Time-Horizon Minority Game [M.L. Hart, P. Jefferies, N.F. Johnson, Phys. A 311, 275 (2002)] and the Parrondo Game
[J.M.R. Parrondo, G.P. Harmer, D. Abbott, Phys. Rev. Lett.
85, 5226 (2000); J.M.R. Parrondo, How to cheat a bad mathematician (ISI, Italy, 1996)], that agents
who optimize their strategy based on past information may actually perform
worse than non-optimizing agents. In other words, low-entropy (more
informative) strategies under-perform high-entropy (or random) strategies.
This provides a precise definition of the “illusion of control” in certain
set-ups a priori defined to emphasize the importance of optimization.
An erratum to this article is available at . 相似文献
15.
M. A. Jafarizadeh R. Sufiani S. Salimi S. Jafarizadeh 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,59(2):199-216
In papers [Jafarizadehn and Salimi, Ann. Phys. 322, 1005 (2007) and J. Phys. A: Math. Gen. 39, 13295 (2006)], the amplitudes of continuous-time quantum
walk (CTQW) on graphs possessing quantum decomposition (QD graphs)
have been calculated by a new method based on spectral
distribution associated with their adjacency matrix. Here in this
paper, it is shown that the CTQW on any arbitrary graph can be
investigated by spectral analysis method, simply by using Krylov
subspace-Lanczos algorithm to generate orthonormal bases of
Hilbert space of quantum walk isomorphic to orthogonal
polynomials. Also new type of graphs possessing generalized
quantum decomposition (GQD) have been introduced, where this is
achieved simply by relaxing some of the constrains imposed on QD
graphs and it is shown that both in QD and GQD graphs, the unit
vectors of strata are identical with the orthonormal basis
produced by Lanczos algorithm. Moreover, it is shown that
probability amplitude of observing the walk at a given vertex is
proportional to its coefficient in the corresponding unit vector
of its stratum, and it can be written in terms of the amplitude of
its stratum. The capability of Lanczos-based algorithm for
evaluation of CTQW on graphs (GQD or non-QD types), has been
tested by calculating the probability amplitudes of quantum walk
on some interesting finite (infinite) graph of GQD type and finite
(infinite) path graph of non-GQD type, where the asymptotic
behavior of the probability amplitudes at the limit of the large
number of vertices, are in agreement with those of central limit
theorem of [Phys. Rev. E 72, 026113 (2005)]. At the end, some applications of the
method such as implementation of quantum search algorithms,
calculating the resistance between two nodes in regular networks
and applications in solid state and condensed matter physics, have
been discussed, where in all of them, the Lanczos algorithm,
reduces the Hilbert space to some smaller subspaces and the
problem is investigated in the subspace with maximal dimension. 相似文献
16.
Yuan-Hua Li Jun-Chang Liu Yi-You Nie 《International Journal of Theoretical Physics》2010,49(10):2592-2599
A new application of the genuinely entangled six-qubit state introduced recently by Tapiador et al. (J. Phys. A 42:415301,
2009) is investigated for the quantum teleportation of an arbitrary three-qubit state and for quantum information splitting (QIS)
of an arbitrary two-qubit state. For QIS, we have shown that it can be completed perfectly with two distinct measurement methods.
In our scheme, the joint Bell-state measurement and the joint multi-qubit measurement are needed. This quantum teleportation
and QIS schemes are deterministic. 相似文献
17.
Within the framework of the two-fluid hydrodynamics of plasmas it is shown that the problem instability of a thin current-carrying
layer admits two limiting cases which allow analytic solutions and complement one another. These limits are analogous to the
well-known shallow-water and deep-water approximations in the fluid mechanical “wave-breaking” instability. In this case,
the long-wave limit coincides with the “quasi-Chaplygin” dynamic system of Bulanov and Sasorov, Fiz Plazmy 4, 746 (1978) [Sov. J. Plasma Phys. 4, 418 (1978)], while the short-wavelength limit corresponds to the phenomenological model of Trubnikov, Usp. Fiz. Nauk 160, 167 (1990) [Sov. Phys. Usp. 33, 87 (1990)], for the clumping of “elementary” currents. In the latter case, strong collapse is unavoidable with the appearance
of current filaments that trap a finite current.
Zh. éksp. Teor. Fiz. 113, 1313–1318 (April 1998) 相似文献
18.
A. Chakrabarti V. K. Dobrev S. G. Mihov 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):135-136
We refute a recent claim in the literature [Czech. J. Phys. 56, 1191 (2006)] of a “new"
quantum deformation of GL(2). 相似文献
19.
We present an improved eavesdropping scheme on the quantum dialogue protocol in lossy channel,which is based on the strategies of W’ojcik [Phys.Rev.Lett.90 157901 (2003)] and ZML [Phys.Lett.A 333 46 (2004)] attack schemes.We show that our attack scheme doubles the domain of Eve’s eavesdropping and Eve can gain more information of the communication with less risk of being detected.Finally,a possible improvement for the dialogue protocol security is proposed. 相似文献
20.
E. Klotins 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):315-320
Nonadiabatic behavior of metastable systems modeled by anharmonic
Hamiltonians is reproduced by the Fokker-Planck and imaginary time
Schr?dinger equation scheme with subsequent symplectic integration.
Example solutions capture ergodicity breaking, reassure the H-theorem of
global stability [M. Shiino, Phys. Rev. A 36, 2393 (1987)],
and reproduce spatially extended response under alternate source fields. 相似文献