Abstract
We consider the eigenvalue problem for a perturbed two-dimensional resonance oscillator. The excitation potential is given by a Hartree-type nonlinearity with a smooth self-action potential. We use asymptotic formulas for the quantum averages to obtain asymptotic eigenvalues and asymptotic eigenfunctions near the lower boundaries of spectral clusters which are formed near the energy levels of the unperturbed operator.
Acknowledgements
The author is grateful to M. V. Karasev for drawing his attention to this problem and also for valuable questions and comments.
Notes
No potential conflict of interest was reported by the author.