This paper is concerned with the breathers of discrete one-dimensional nonlinear Schrödinger equations in inhomogeneous media. By using a constrained minimization approach known as the Nehari variational principle or the Nehari manifold approach, we obtain the existence of nontrivial breathers.
"Breathers of Discrete One-dimensional Nonlinear Schrödinger Equations in Inhomogeneous Media." Taiwanese J. Math. 23 (3) 675 - 690, June, 2019. https://doi.org/10.11650/tjm/180804