共查询到20条相似文献,搜索用时 31 毫秒
1.
Hong-yi Fan Yue Fan 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(2):233-238
Starting from the Einstein-Podolsky-Rosen entangled state representations of continuous variables we derive a new formulation
of complex fractional Fourier transformation (CFFT). We find that two-variable Hermite polynomials are just the eigenmodes
of the CFFT. In this way the CFFT is linked to the appropriate operator transformation between two kinds of entangled states
in the context of quantum mechanics. In so doing, the CFFT of quantum mechanical wave functions can be derived more directly
and concisely.
Received 21 February 2002 / Received in final form 1st June 2002 Published online 24 September 2002
RID="*"
ID="*"Work supported by National Natural Science Foundation of China under grant 10175057 and the President Foundation of
Chinese Academy of Science.
RID="a"
ID="a"e-mail: fhym@ustc.edu.cn 相似文献
2.
Y. Zhang K. Kasai M. Watanabe 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(3):361-366
We propose a novel quantum switch teleportation with a continuous variable, which can teleport a quantum state to two different
receivers alternatively, using a pair of two-mode squeezed lights as the quantum switching to manipulate the transmission
route. In this scheme, the EPR entangled beams shared by sender and receivers are produced by mixing a pair of two-mode squeezed
lights on one beamsplitter and separating them by using a polarizing beam splitter. The teleportation capability of this system
is examined by the criteria proposed by Ralph and Lam [#!ralph!#] from a small signal quantum optical point of view.
Received 20 May 2002 / Received in final form 29 July 2002 Published online 24 September 2002
RID="a"
ID="a"e-mail: zhangyun@crl.go.jp 相似文献
3.
C.H. Raymond Ooi K.-P. Marzlin J. Audretsch 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):259-267
A general scheme for reducing the center-of-mass entropy is proposed. It is based on the repetition of a cycle, composed of
three concepts: velocity selection, deceleration and irreversible accumulation. Well-known laser techniques are used to represent
these concepts: Raman π-pulse for velocity selection, STIRAP for deceleration, and a single spontaneous emission for irreversible
accumulation. No closed pumping cycle nor repeated spontaneous emissions are required, so the scheme is applicable to cool
a molecular gas. The quantum dynamics are analytically modelled using the density matrix. It is shown that during the coherent
processes the gas is translationally cooled. The internal states serve as an entropy sink, in addition to spontaneous emission.
This scheme provides new possibilities to translationally laser-cool molecules for high precision molecular spectroscopy and
interferometry.
Received 25 June 2002 / Received in final form 28 September 2002 Published online 12 November 2002
RID="a"
ID="a"e-mail: ooi@spock.physik.uni-konstanz.de
RID="b"
ID="b"e-mail: Peter.Marzlin@uni-konstanz.de
RID="c"
ID="c"e-mail: Juergen.Audretsch@uni-konstanz.de 相似文献
4.
G. De Ninno D. Fanelli C. Bruni M.E. Couprie 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):269-277
The temporal dynamics of a storage-ring Free Electron Laser is here investigated with particular attention to the case in
which an external modulation is applied to the laser-electron beam detuning. The system is shown to produce bifurcations as
well as chaotic regimes. The peculiarities of this phenomenon with respect to the analogous behaviour displayed by conventional
laser sources are pointed out. Theoretical results, obtained by means of a phenomenological model reproducing the evolution
of the main statistical parameters of the system, are shown to be in a good agreement with experiments carried out on the
Super-ACO Free Electron Laser.
Received 27 March 2002 / Received in final form 17 July 2002 Published online 21 January 2003
RID="a"
ID="a"Present address: Sincrotone Trieste, 34012 Trieste, Italy.
RID="b"
ID="b"e-mail: fanelli@nada.kth.se 相似文献
5.
R. Fiore A. Flachi L.L. Jenkovszky A.I. Lengyel V.K. Magas 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):505-515
An explicit model realizing parton-hadron duality and fitting the data is suggested. Complex nonlinear Regge trajectories
are important ingredients of the model. The inclusion of Δ and N* trajectories should account for all resonances in the direct channel. The exotic trajectory is responsible for the smooth
background.
Received: 7 June 2002 / Accepted: 3 July 2002 / Published online: 10 December 2002
RID="a"
ID="a"e-mail: fiore@cs.infn.it
RID="b"
ID="b"e-mail: flachi@ifae.es
RID="c"
ID="c"e-mail: jenk@gluk.org
RID="d"
ID="d"e-mail: sasha@len.uzhgorod.ua
RID="e"
ID="e"e-mail: vladimir@cfif.ist.utl.pt
Communicated by V.V. Anisovich 相似文献
6.
R. Capovilla C. Chryssomalakos J. Guven 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(2):163-166
We examine the equilibria of a rigid loop in the plane, characterized by an energy functional quadratic in the curvature,
subject to the constraints of fixed length and fixed enclosed area. Whereas the only non self-intersecting equilibrium corresponding
to the fixed length constraint is the circle, the area constraint gives rise to distinct equilibria labeled by an integer.
These configurations exhibit self-intersections and bifurcations as the area is reduced. In addition, not only can the Euler-Lagrange
equation be integrated to provide a quadrature for the curvature but the embedding itself can be expressed as a local function
of the curvature. Perturbations connecting equilibria are shown to satisfy a first order ODE which is readily solved. Analytical
expressions for the energy as a function of the area are obtained in the limiting regimes.
Received 18 October 2001 / Received in final form 31 May 2002 Published online 2 October 2002
RID="a"
ID="a"e-mail: capo@fis.cinvestav.mx
RID="b"
ID="b"e-mail: chryss@nuclecu.unam.mx
RID="c"
ID="c"e-mail: jemal@nuclecu.unam.mx 相似文献
7.
S. Kazamias F. Weihe D. Douillet C. Valentin T. Planchon S. Sebban G. Grillon F. Augé D. Hulin Ph. Balcou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(3):353-359
We report a systematic study of high order harmonic generation with an infrared laser apertured by an iris, as a function
of the aperture size. Measurements were made of harmonic generation efficiency for different gas species, laser energies and
focal geometries. Harmonic efficiencies as a function of aperture show a characteristic peaked shape, which is independent
of gas species and harmonic order. A one dimensional, time dependent simulation of harmonic generation in a gas cell, taking
into account experimentally measured transverse coherence of the laser, closely reproduces the observed behaviours. We show
that the aperture diameter which maximizes harmonic yield is the result of a compromise between considerations of focal geometry
and ionization (which favour small apertures); and harmonic dipole amplitude and phase (which favour large apertures).
Received 31 May 2002 Published online 24 September 2002
RID="a"
ID="a"e-mail: kazamias@ensta.fr
RID="b"
ID="b"UMR 7639 du CNRS 相似文献
8.
A. Borah S. Ghosh S. Nandy 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(2):221-225
The novel inelastic collision properties of two-soliton interaction for an n-component coupled higher order nonlinear Schr?dinger equation are studied. Some interesting features of three soliton interactions,
related to the integrability of the n-component coupled higher order nonlinear Schr?dinger equation are also discussed.
Received 17 April 2002 Published online 2 October 2002
RID="a"
ID="a"e-mail: abhijit@iitg.ernet.in
RID="b"
ID="b"e-mail: sasanka@iitg.ernet.in
RID="c"
ID="c"e-mail: sudipta@iitg.ernet.in 相似文献
9.
A model is proposed that treats electrons at surfaces as a combination of two-dimensional and three-dimensional degrees of
freedom. This yields a simple formula for the surface state induced resonant enhancement of the transfer of electrons through
a surface. The model also yields analytic approximations for the transition between two-dimensional and three-dimensional
distance laws in the correlations between electrons in surface states.
Received 6 August 2002 Published online 31 October 2002
RID="a"
ID="a"e-mail: rainer@sask.usask.ca 相似文献
10.
The $-game 总被引:1,自引:0,他引:1
J. Vitting Andersen D. Sornette 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(1):141-145
We propose a payoff function extending Minority Games (MG) that captures the competition between agents to make money. In
contrast with previous MG, the best strategies are not always targeting the minority but are shifting opportunistically between
the minority and the majority. The emergent properties of the price dynamics and of the wealth of agents are strikingly different
from those found in MG. As the memory of agents is increased, we find a phase transition between a self-sustained speculative
phase in which a “stubborn majority” of agents effectively collaborate to arbitrage a market-maker for their mutual benefit
and a phase where the market-maker always arbitrages the agents. A subset of agents exhibit a sustained non-equilibrium risk-return
profile.
Received 5 June 2002 / Received in final form 21 November 2002 Published online 27 January 2003
RID="a"
ID="a"e-mail: sornette@unice.fr
RID="b"
ID="b"CNRS UMR7536
RID="c"
ID="c"CNRS UMR6622 相似文献
11.
Xin-Hai Liu Xue-Hua Wang Ben-Yuan Gu 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(3):339-342
We investigate the effects of spatial asymmetry, tunneling coupling, and exchange-correlation correction on the plasmon modes
in asymmetric double quantum well (DQW) structures in a time-dependent local-density approximation. Special attention is paid
to the properties of the ω
- mode which is always damped in symmetric DQW systems. In addition, the results on the spectral weight of the excitations
are also presented. In general, all the modes carry finite spectral weights and should be observable in resonant inelastic
light scattering experiments for the specified values of the parameters.
Received 2 July 2002 Published online 19 December 2002
RID="a"
ID="a"e-mail: c412-1@aphy.iphy.ac.cn 相似文献
12.
In Rydberg atoms subject to static and harmonic collinear electric fields, intrashell transition can be induced by the first
order perturbation from a small perpendicular electric or magnetic field, or by effects of the second order in the major fields.
Both mechanisms lead to resonances that are suppressed under certain conditions, and high-frequency interference oscillations
in case of non-adiabatic field switching. Recent measurements of microwave ionization signals show very rich and fascinating
structures similar to the ones predicted for intrashell mixing. We show that the observed ionization structures may be explained
by diabatic electric-field ionization and the consistent use of perturbation theory for intrashell mixing. In particular,
the dominant oscillation frequency is successfully interpreted in terms of interference between first and second order transition
amplitudes. New predictions are provided. The present approach gives a comprehensive picture of intrashell transitions, which
may be tested in future experiments designed to observe such transitions directly.
Received 2 May 2002 / Received in final form 23 September 2002 Published online 21 January 2003
RID="a"
ID="a"e-mail: Valentin.Ostrovsky@pobox.spbu.ru
RID="b"
ID="b"e-mail: horsdal@ifa.au.dk 相似文献
13.
L.F. Lemmens F. Brosens J.T. Devreese 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(2):195-202
A full analysis of domain structure using a micromagnetic model is developed in order to get a clear insight into the behaviour
of transverse initial susceptibility as a function of dc applied field for thin films and bilayers exhibiting both in-plane
and perpendicular anisotropy. The numerical simulations are in good agreement with available experimental results in case
of single layers with the so-called stripe domain pattern while some predictions are done for bilayers. As the main result,
it is shown that in low field, the transverse initial susceptible cannot be interpreted without the knowledge of the static
domain pattern while, above saturation, it is only affected by the in-plane anisotropy.
Received 10 October 2002 Published online 4 February 2003
RID="a"
ID="a"e-mail: ml@lpmtm.univ-paris13.fr
RID="b"
ID="b"UMR CNRS 8634 相似文献
14.
K. Knorr L. Ehm M. Hytha B. Winkler W. Depmeier 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(3):297-303
The high-pressure behaviour of PbS was investigated by angular dispersive X-ray powder diffraction up to pressures of 6.8
GPa. Experiments were accompanied by first principles calculations at the density functional theory level. By combining both
methods reliable data for the elastic properties of rock-salt type α- and high-pressure β-PbS could be obtained. β-PbS could be determined to crystallise in the CrB-type (B33), with space group Cmcm. The reversible ferro-elastic α/β transition is of first order. It is accompanied by a large volume discontinuity of about 5% and a coexistence region of the
two phases. A gliding mechanism of {001} bilayers along one of the cubic 〈110〉 directions governs the phase transition which can be described in terms of group/subgroup relationships via a common subgroup, despite its reconstructive character. The quadrupling of the primitive unit cell indicates a wave vector
(0, 0,π/
a
) on the Δ-line of the Brillouin zone.
Received 11 October 2002 Published online 14 February 2003
RID="a"
ID="a"Also at: Institute of Physics of the Czech Academy of Sciences, Cukrovarnicka 10, 16253 Praha 6, Czech Republic e-mail: knorr@min.uni-kiel.de
RID="b"
ID="b"Present address: University of Cambridge, Cavendish Laboratory (TCM), Madingley Road, Cambridge CB3 0HE, UK
RID="c"
ID="c"Present address: Johann-Wolfgang Goethe Universit?t, Mineralogisches Institut, Kristallographie, Senckenberganlage 30, D 60054 Frankfurt a.M.,
Germany 相似文献
15.
B. Leblanc E. Lutton F. Axel 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(4):619-628
We present the first application of Genetic Algorithms to the analysis of data from an aperiodically ordered system, high
resolution X-Ray diffraction spectra from multilayer heterostructures arranged according to a deterministic or random scheme.
This method paves the way to the solution of the “inverse problem”, that is the retrieval of the generating disorder from
the investigation of the spectra of an unknown sample having non crystallographic, non quasi-crystallographic order.
Received 18 March 2002 / Received in final form 3 July 2002 Published online 31 October 2002
RID="a"
ID="a"e-mail: Evelyne.Lutton@inria.fr
RID="b"
ID="b"CNRS UMR 8502 相似文献
16.
D. Bucurescu A. Gadea Ghe. Căta-Danil I. Căta-Danil M. Ivaşcu N. Mărginean C. Rusu L. Stroe C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):469-474
High-spin states in the 97Tc nucleus have been studied by in-beam γ-ray spectroscopy with the reaction 82Se(19F,4nγ) at 68 MeV incident energy. Excited states have been observed up to about 8 MeV excitation and spin 43/2. The observed
level scheme is compared with results of shell model calculations.
Received: 22 November 2002 / Accepted: 23 December 2002 / Published online: 18 March 2003
RID="a"
ID="a"e-mail: bucurescu@tandem.nipne.ro
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="c"
ID="c"Present address: Università di Padova, Padova, Italy.
Communicated by C. Signorini 相似文献
17.
We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the
one of the top quark, at future Linear Colliders operating in mode at the TeV energy scale. Final states with one or two bosons are considered, as produced by both tree- and loop-level interactions.
Received: 8 November 2002 / Revised version: 12 February 2003 / Published online: 13 May 2003
RID="a"
ID="a" e-mail: stefano.moretti@cern.ch
RID="b"
ID="b" e-mail: kanemu@post.kek.jp 相似文献
18.
T. Dobrowolski 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(2):269-271
The production of topological defects during a quench in a φ4 model is investigated. The influence of a spatially correlated noise on defect production in two and three dimensions is
demonstrated.
Received 28 August 2001 / Received in final form 11 February 2002 Published online 2 October 2002
RID="a"
ID="a"Paper supported in part by ESF “COSLAB” Programme
RID="b"
ID="b"e-mail: sfdobrow@kinga.cyf-kr.edu.pl 相似文献
19.
D.A. Trifonov 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(2):349-353
A survey on the generalizations of Heisenberg uncertainty relation and a general scheme for their entangled extensions to
several states and observables is presented. The scheme is illustrated on the examples of one and two states and canonical
quantum observables, and spin and quasi-spin components. Several new uncertainty relations are displayed.
Received 10 October 2001 / Received in final form 6 March 2002 Published online 2 October 2002
RID="a"
ID="a"e-mail: dtrif@inrne.bas.bg 相似文献
20.
J. Bylander I. Robert-Philip I. Abram 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):295-301
Two independent photons, produced through the spontaneous emission of two separate emitters subject to uncorrelated dephasing
processes, can display two-photon interference (i.e. coalescence into a two-photon state) when they are incident simultaneously on a beamsplitter, in a manner analogous to that
of twin photons produced through degenerate parametric fluorescence. The presence of dephasing processes, however, reduces
the interference contrast (i.e. the probability of coalescence), by the ratio of the coherence time to the lifetime of the emitter.
Received 9 September 2002 Published online 17 December 2002
RID="a"
ID="a"e-mail: izo.abram@lpn.cnrs.fr 相似文献