Strong Instability of Solitary Waves for Inhomogeneous Nonlinear
This paper studies the inhomogeneous nonlinear Schrödinger equations,
which may model the propagation of laser beams in nonlinear optics.
Using the cross-constrained variational method, a sharp condition for
global existence is derived. Then, by solving a variational problem, the
strong instability of solitary waves of this equation is proved.