55 research outputs found
Closed Form Formulas for the Rosen-morse and Manning- Rosen Rotation-vibration Intensities From Ladder Operator Considerations
Inter-isotope determination of ultracold rubidium interactions from three high-precision experiments
Combining the measured binding energies of four of the most weakly bound
rovibrational levels of the Rb molecule with the results of two
other recent high-precision rubidium experiments, we obtain exceptionally
strong constraints on the atomic interaction parameters in a highly model
independent analysis. The comparison of Rb and Rb data, where the
two isotopes are related by a mass scaling procedure, plays a crucial role.
Using the consistent picture of the interactions that thus arises we are led to
predictions for scattering lengths, clock shifts, Feshbach resonance fields and
widths with an unprecedented level of accuracy. To demonstrate this, we predict
two Feshbach resonances in mixed-spin scattering channels at easily accessible
magnetic field strengths, which we expect to play a role in the damping of
coherent spin oscillations
Exact asymptotic form of the exchange interactions between shallow centers in doped semiconductors
The method developed in [L. P. Gor'kov and L. P. Pitaevskii, Sov. Phys. Dokl.
8, 788 (1964); C. Herring and M. Flicker, Phys. Rev. 134, A362 (1964)] to
calculate the asymptotic form of exchange interactions between hydrogen atoms
in the ground state is extended to excited states. The approach is then applied
to shallow centers in semiconductors. The problem of the asymptotic dependence
of the exchange interactions in semiconductors is complicated by the multiple
degeneracy of the ground state of an impurity (donor or acceptor) center in
valley or band indices, crystalline anisotropy and strong spin-orbital
interactions, especially for acceptor centers in III-V and II-VI groups
semiconductors. Properties of two coupled centers in the dilute limit can be
accessed experimentally, and the knowledge of the exact asymptotic expressions,
in addition to being of fundamental interest, must be very helpful for
numerical calculations and for interpolation of exchange forces in the case of
intermediate concentrations. Our main conclusion concerns the sign of the
magnetic interaction -- the ground state of a pair is always non-magnetic.
Behavior of the exchange interactions in applied magnetic fields is also
discussed
Expansions for the eigenvalues of three-term recurrence relations. Two applications in molecular physics
Approximate expressions for the eigenvalue of a three-term recurrence relation with a
general form describing various physical problems are proposed. Their range of availability is
examined by comparison with exact values for two different problems: the bound and
continuum states of monoelectronic diatomic ions and the Schrödinger equation describing
molecular alignment in intense laser fields. For each case, very good predictions have been
obtained, which may be useful as initial values in iterative procedures for deriving exact
solutions
Etude du deuxieme spectrometre de masse pour l'analyse des fragments d'ADN produits apres intersection avec un faisceau de protons
Logiciel TRAGRA permettant une sortie graphique des resultats obtenus a partir du programme TRANSPORT modifie
Expansions for the eigenvalues of three-term recurrence relations. Two applications in molecular physics
Étude Du Lieu De Formation Des Ions Dans Une Source Penning En Fonction De La Forme Du Champ Magnétique Par La Méthode De Monte-Carlo
- …