Abstract
In this paper, one-dimensional derivative Schrödinger equation, with periodic boundary condition is considered. It is proved that the above equation admits a Whitney smooth family of small amplitude, quasi-periodic solutions with two-dimensional Diophantine frequencies. The proof is based on infinite-dimensional Kolmogorov-Arnold-Moser (KAM) theory, partial Birkhoff normalization and scaling skills.
Acknowledgements
We would like to thank the referees for their invaluable suggestions.
Disclosure statement
No potential conflict of interest was reported by the authors.