Title
Unified QLM for regular and arbitrary singular potentials.
Abstract
A parameterless numerical implementation of the Quasilinearization Method (QLM) is constructed and tested to 21–25 digits precision to give quadratically convergent energies E of the Klauder effect exhibiting spiked harmonic oscillator with the λ/rα or exp(λ/rα) type spikes in a Riccati reformulation of the Schrödinger equation. The radial solution is uniformly quadratic convergent to the same precision as E, except in the small minorization interval where the self-correcting property of QLM assures geometric convergence like in the Picard algorithm to about 12–16 digits, sufficient not to affect the convergence of E, confirming what is expected on physical grounds. It was shown before that for regular potentials, immediate onset of quadratic convergence is guaranteed by the initial iteration of the WKB form, and that for quadratic convergence of E for power-type spikes it suffices to augment this by a nonlinear integration point distribution and by minorization of (negative) solution values. The form of the Riccati equation used allows the minorization function to easily be formally defined over the entire interval, without the need for a cutoff radius of application, and dependence on its scale factor is plateau-like and negligible.
Year
DOI
Venue
2014
10.1016/j.amc.2014.08.051
Applied Mathematics and Computation
Keywords
Field
DocType
Quasilinearization,Singular potentials,Spiked oscillator,Exponentially spiked oscillator,Nonlinear perturbation theory,Klauder effect
Scale factor,Convergence (routing),Mathematical optimization,Quadratic growth,Mathematical analysis,Schrödinger equation,Quadratic equation,WKB approximation,Riccati equation,Rate of convergence,Mathematics
Journal
Volume
ISSN
Citations 
246
0096-3003
0
PageRank 
References 
Authors
0.34
3
1
Name
Order
Citations
PageRank
Rajmund Krivec100.34