Spectral characteristics for a spherically confined $-a/r+br^2$ potential.

*(English)* Zbl 1215.81144
Summary: We consider the analytical properties of the eigenspectrum generated by a class of central potentials given by $V(r)=-a/r + br^2$, $b > 0$. In particular, scaling, monotonicity, and energy bounds are discussed. The potential $V(r)$ is considered both in all space, and under the condition of spherical confinement inside an impenetrable spherical boundary of radius $R$. With the help of the asymptotic iteration method, several exact analytic results are obtained which exhibit the parametric dependence of energy on $a$, $b$, and $R$, under certain constraints. More general spectral characteristics are identified by use of a combination of analytical properties and accurate numerical calculations of the energies, obtained by both the generalized pseudo-spectral method, and the asymptotic iteration method. The experimental significance of the results for both the free and confined potential $V(r)$ cases are discussed.

##### MSC:

81V45 | Applications of quantum theory to atomic physics |

81Q05 | Closed and approximate solutions to quantum-mechanical equations |

81Q10 | Selfadjoint operator theory in quantum theory, including spectral analysis |

39B12 | Iterative and composite functional equations |

81T80 | Simulation and numerical modelling (quantum field theory) |