Strong-coupling expansions for the PT-symmetric oscillators V(x)=a(ix)+b(ix)(2)+c(ix)(3)

Authors
Fernandez, FM Guardiola, R Ros, J Znojil, M
Citation
Fm. Fernandez et al., Strong-coupling expansions for the PT-symmetric oscillators V(x)=a(ix)+b(ix)(2)+c(ix)(3), J PHYS A, 31(50), 1998, pp. 10105-10112
Citations number
30
Categorie Soggetti
Physics
Journal title
JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL
ISSN journal
03054470 → ACNP
Volume
31
Issue
50
Year of publication
1998
Pages
10105 - 10112
Database
ISI
SICI code
0305-4470(199812)31:50<10105:SEFTPO>2.0.ZU;2-I
Abstract
We study the traditional problem of convergence of perturbation expansions when the hermiticity of the Hamiltonian is relaxed to a weaker PT symmetry. An elementary and quite exceptional cubic anharmonic oscillator is chosen as an illustrative example of such models. We describe its perturbative fea tures paying particular attention to the strong-coupling regime. Efficient numerical perturbation theory proves suitable for such a purpose.