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81.
We study the Schrödinger equation with potentials admitting quasinormal modes using the asymptotic iteration method (AIM). We also study non-Hermitian PT symmetric potentials using AIM. The spectra, in all cases, are found to be in excellent agreement with exact results. 相似文献
82.
Josephson oscillation of a superfluid Fermi gas 总被引:1,自引:0,他引:1
S. K. Adhikari 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(3):413-419
Using the complete numerical solution of a time-dependent
three-dimensional mean-field model we
study the Josephson oscillation of a superfluid Fermi gas (SFG) at zero temperature formed in a combined axially-symmetric
harmonic plus one-dimensional periodic optical-lattice (OL) potentials after displacing the harmonic trap along the axial
OL
axis. We study the dependence of Josephson frequency on the strength of the OL potential. The Josephson frequency decreases
with increasing strength as found in the experiment of Cataliotti et al. [Science 293, 843 (2001)] for a Bose-Einstein condensate and of the experiment of Pezzè et al. [Phys. Rev. Lett. 93, 120401 (2004)] for an ideal Fermi gas. We demonstrate a
breakdown of Josephson oscillation in the SFG for a large displacement
of the harmonic trap. These features of Josephson oscillation of a SFG can be tested experimentally. 相似文献
83.
We systematically investigate the motion of slowly moving
matter--wave gap solitons in a nonlinear potential, produced by the
weak random spatial variation of the atomic scattering length. With
the weak randomness, we construct an effective-particle theory to
study the motion of gap solitons. Based on the effective-particle
theory, the effect of the randomness on gap solitons is obtained, and
the motion of gap solitons is finally solved. Moreover, the analytic
results for the general behaviours of gap soliton motion, such as the
ensemble-average speed and the reflection probability depending on
the weak randomness are obtained. We find that with the increase of
the random strength the ensemble-average speed of gap solitons
decreases slowly where the reduction is proportional to the variance
of the weak randomness, and the reflection probability becomes
larger. The theoretical results are in good agreement with the
numerical simulations based on the Gross--Pitaevskii equation. 相似文献
84.
A. B. Bhattacherjee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(3):499-506
We study the effect of a one dimensional optical superlattice on the superfluid properties (superfluid fraction, number squeezing,
dynamic structure factor) and the quasi-momentum distribution of the Mott-insulator. We show that due to the secondary lattice,
there is a decrease in the superfluid fraction and the number fluctuation. The dynamic structure factor which can be measured
by Bragg spectroscopy is also suppressed due to the addition of the secondary lattice. The visibility of the interference
pattern (the quasi-momentum distribution) of the Mott-insulator is found to decrease due to the presence of the secondary
lattice. Our results have important implications in atom interferometry and quantum computation in optical lattices. 相似文献
85.
We propose a two-color scheme of atom waveguides and one-dimensional (1D) optical lattices using evanescent wave fields of different transverse modes around an optical micro/nano-fiber. The atom guide potential can be produced when the optical fiber carries a red-detuned light with TE01 mode and a blue-detuned light with HEll mode, and the 1D optical lattice potential can be produced when the red-detuned light is transformed to the superposition of the TE01 mode and HE11 mode. The two trapping potentials can be transformed to each other for accurately controlling mode transformation for the red-detuned light. This might provide a new approach to realize flexible transition between the guiding and trapping states of atoms. 相似文献
86.
Neji Khelifi 《Journal of Russian Laser Research》2008,29(3):274-287
Adiabatic and diabatic study for all the states dissociating below the ionic limit [i.e., Na (3s, 3p, 4s, 3d, 4p, 5s, 4d,
and 4f) + H (1s)] in 1Σ+ and 3Σ+ symmetries are presented. Adiabatic results are also reported for 1,3Π and 1,3Δ symmetries. Pseudo-potential, operatorial core-valence correlation, and full valence CI approaches combined with an efficient
diabatization procedure are used in these ab initio calculations. Our vibrational-level spacings and spectroscopic constants
are in good agreement with the available experimental data for the low-lying states. Diabatic potentials and dipole moments
are analyzed, revealing the strong imprint of the ionic state in the 1Σ+ adiabatic states. The hydrogen electron affinity correction was taken into account by the use of the efficient diabatization
method. This leads to a better agreement with the available experimental data. Experimental suggestions are also given for
the higher excited states based on their unusual behavior. 相似文献
87.
In this paper, we study an L
2 version of the semiclassical approximation of magnetic Schrödinger operators with invariant Morse type potentials on covering spaces of compact manifolds. In particular, we are able to establish the existence of an arbitrary large number of gaps in the spectrum of these operators, in the semiclassical limit as the coupling constant goes to zero. 相似文献
88.
Marius Mitrea 《Proceedings of the American Mathematical Society》2002,130(9):2599-2607
Let be a second order, (variable coefficient) elliptic differential operator and let , , 0$">, satisfy in the Lipschitz domain . We show that can exhibit more regularity on Besov scales for which smoothness is measured in with . Similar results are valid for functions representable in terms of layer potentials.
89.
90.
A formula of a radial derivative
is obtained with the aid of derivatives with respect to and to of the functions closely connected with the spherical Poisson integral
and the boundary values are determined for
. The boundary values are also found for partial derivatives with respect to the Cartesian coordinates
. 相似文献