3,066 research outputs found
Ground-state properties of bosons in three- and two-dimensional traps
We study trapped systems of bosons at zero temperature in three and two
dimensions. Conditions are fulfilled for the application of Gross-Pitaevskii
theory with a positive scattering length. Series expansions for ground-state
properties are obtained in both the noninteracting and the strong-coupling
(Thomas-Fermi) limits. From these expansions, analytic estimates are presented
in the form of two-point Pad\'e approximants. We explicitly show the
approximants for the total energy per particle and the chemical potential.Comment: LaTeX, 4 pages, 3 ps figure
Renormalised perturbative series for the impurity levels in a quantum well
The energy levels of an impurity center in a deep quantum well of width L and
depth g are studied analytically . Renormalised perturbative series are
constructed in the regions g L^ > 1. Maximal binding energy and
wave function deformation to a quasi-twodimensional function are found to occur
at a certain L_c satisfying sqrt{g} L_c ~ 1. Similar results may be obtained
for the impurity in a quantum wire, in a dot or in a multiwell structure.Comment: 11 pages. LaTeX. 3 figures not include
The NIST compilation of ionization potentials revisited (I): From He-like to Xe-like ions
The National Institute of Standards and Technology (NIST) database on
ionization potentials for neutral atoms and ions is examined. For each
isoelectronic sequence, we construct a regularized perturbative series that
exactly matches the large- and regions. Comparison of the
NIST data with this series allows the identification of problematic values in
the reported data.Comment: 19 pages, 43 figure
- …