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51.
A proposal is presented for teleporting Schrding-cat states. The process of the teleportation is achieved through the dispersive atom-cavity-field interaction. In this proposal, only measurement on the cavity field and on the singlet atomic states are used. 相似文献
52.
J.O. Andersen 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(4):389-396
We consider an interacting homogeneous Bose gas at zero temperature in two spatial dimensions. The properties of the system
can be calculated as an expansion in powers of g, where g is the coupling constant. We calculate the ground state pressure and the ground state energy density to second order in the
quantum loop expansion. The renormalization group is used to sum up leading and subleading logarithms from all orders in perturbation
theory. In the dilute limit, the renormalization group improved pressure and energy density are expansions in powers of the
T
2B and T
2Bln(T
2B), respectively, where T
2B is the two-body T-matrix.
Received 19 April 2002 Published online 13 August 2002 相似文献
53.
提出一种利用 GHZ态实现多原子缠结态的量子隐形传态方案 .当作为量子通道的 GHZ态含有一个单模高 Q腔时 ,大大地简化了量子稳形传态中的联合测量过程 相似文献
54.
The possibility that pairs of quarks will form diquark clusters in the regime above deconfinement transition for hadron matter
at finite density is revisited. Here we present the results on the diquark-diquark (dq-dq) interaction in the framework of
constituent quark model taking account of spin, isospin and color degrees of freedom in the spirit of generalized Pauli principle.
By constructing the appropriate spin and color states of the dq-dq clusters we compute the expectation values of the interaction
Hamiltonian involving pairwise quark—quark interaction. We find that the effective interaction between two diquark clusters
is quite sensitive to different configurations characterized by color and spin states, obtained after the coupling of two
diquark states. The value of the coupling parameter for a particular color—spin state, i.e., -3, 1 is compared to the one
obtained earlier by Donoghue and Sateesh,Phys. Rev.
D38, 360 (1988) based on the effective Φ4-theory. This new value of λ derived for different color-spin dq-dq states, may lead to several important implications in
the studies of diquark star and diquark gas. 相似文献
55.
E. Liénard G. Ban J. Blieck D. Durand F. Duval X. Fléchard M. Herbane M. Labalme Y. Lemière F. Mauger A. Méry O. Naviliat-Cuncic D. Rodríguez J. C. Thomas 《Hyperfine Interactions》2006,172(1-3):29-33
We report on the status of the LPCTrap experiment, devoted to measure the β–ν angular correlation in the pure Gamow–Teller
decay of 6He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The
6He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to
deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this
experiment. Up to 105 coincidences were recorded during a second run in 2006. 相似文献
56.
A simple method of determining ultra-trace Au in natural water was presented by using graphite furnace atomic absorption spectrophotometry (GFAAS) after in situ enrichment with thiol cotton fiber (TCF). The sample solution was adjusted to pH 1.5-2.0 with HCl, then the water sample was passed through a column packed with 0.10-0.20 g TCF and the flow rate was controlled at 20-40 ml min−1. The effects of interferences, such as complexing and oxidizing agents and other elements adsorbed on TCF were overcome by chemical treatments prior to the desorption of Au. The adsorbed Au was adsorbed with 2.0 ml hot acid, then it was extracted with 1.00 ml methyl isobutylketone (MIBK). For a 5 l water sample, the detection limit of Au is 0.02 ng l−1. The relative standard deviation (R.S.D.) for the determination of 1.44 ng l−1 Au was 9.4%.The method was applied to determine ultra-trace Au both in suspended phase and soluble phase in natural water, the concentrations of total Au in natural water samples range from 0.51 to 67.82 ng l−1. The recovery of added 0.50-6.00 ng l−1 Au was 80-95%. The method is useful in prospecting for Au deposits by means of hydrogeochemical methods. The enrichment is carried out in the field, and then the determination of Au is completed later in the laboratory. 相似文献
57.
Jing-Hui Qiu 《Journal of Mathematical Analysis and Applications》2004,292(2):459-469
A weaker Mackey topology, infra-Mackey topology, is introduced. For an infra-Mackey space, dual local quasi-completeness, c0-quasi-barrelledness, Ruess' property (quasi-L) and C-quasi-barrelledness are equivalent to each other. Inspired by the definition of Mazur spaces, locally convex spaces are classified according to various conditions ensuring linear functionals continuous. In the classification, every class of special locally convex spaces is characterized by some completeness of the duals. From this, some new characterizations of quasi-barrelledness and barrelledness are given. 相似文献
58.
P. Mun F. C. Fonseca R. Muccillo R. F. Jardim 《Physica C: Superconductivity and its Applications》2003,390(4):363-373
A systematic study of the magnetic hysteresis in transport properties of polycrystalline YBa2Cu3O7−δ–Ag compounds has been made based on two kinds of measurements at 77 K and under applied magnetic fields up to 30 mT: critical current density Jc(Ba) and magnetoresistance R(Ba). The R(Ba) curves show a minimum in their decreasing branch occurring at B=Bmin which was found to be both the excitation current Iex and the maximum applied magnetic field Bam dependent. In addition, for a certain value of Bam>5 mT, we have observed that Bmin increases with increasing Iex and reaches a saturation value. The Jc(Ba) curves show a maximum in decreasing applied magnetic fields occurring at B=Bmax. We have also found that Bmax increases with increasing Bam and reaches a saturation value. The minimum in the R(Ba) and the maximum in Jc(Ba) curves were found to be related to the trapped flux within the grains. All the experimental results are discussed within the context of the flux dynamics and transport mechanisms in these high-Tc materials. 相似文献
59.
Wenbing Hu Alexander Buzin Jar‐Shyong Lin Bernhard Wunderlich 《Journal of Polymer Science.Polymer Physics》2003,41(4):403-417
The annealing at 373 K of ultrastrong, gel‐spun polyethylene (PE) has been studied. At this temperature, the fibers show no significant shrinkage. Still, a significant decrease in the mechanical properties is observed. The fibers have been analyzed with differential scanning calorimetry (DSC), temperature‐modulated differential scanning calorimetry (TMDSC), atomic force microscopy (AFM), and small‐angle X‐ray scattering (SAXS). During the annealing, the glass transition of the intermediate phase is exceeded, as shown by DSC. When split for structure analysis by AFM, the annealed fibers undergo plastic deformation around the base fibrils instead of brittle fracture. The quasi‐isothermal TMDSC experiments are compared to the minor structural changes seen with SAXS and AFM. The loss of performance of the PE fibers at 373 K is suggested to be caused by the oriented intermediate phase, and not by major changes in the structure or morphology. The overall metastable, semicrystalline structure is shown by TMDSC to posses local regions that can melt reversibly. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 403–417, 2003 相似文献
60.
We give an account of the appearance and first developments of the statistical model of atoms proposed by Thomas and Fermi, focusing on the main results achieved by Fermi and his group in Rome. Particular attention is addressed to the unknown contribution to this subject by Majorana, anticipating some important results reached later by leading physicists. 相似文献