Stability of Solitary Waves of the (Phi/sup 3/ - phi/sup 5/)-Nonlinear Schroedinger Equation under Non-Vanishing Boundary Conditions

摘要

The stability of the bubble-like soliton solution of the equation is examined: ipsi/sub t/+psi/sub xx/+ alpha psi+psi/psi/sup 2/-psi/psi/sup 4/=0, where psi(x, t) -> psi /sup +-/=const as x -> +- infinity. The analysis of the above equation linearized about the static bubble is reduced to an eigenvalue problem for two coupled Schroedinger operators. This problem is found to possess a bound state solution for all a. Cosequently, there exist exponentially growing perturbations, and motionless bubble appears to be always unstable. The dependence of the growth rate on a is numerically calculated. 14 refs. (Atomindex citation 18:015246)