Nonlinear Stationary States in PT-Symmetric Lattices

  title={Nonlinear Stationary States in PT-Symmetric Lattices},
  author={Panayotis G. Kevrekidis and Dmitry E. Pelinovsky and Dmitry Tyugin},
  journal={SIAM J. Appl. Dyn. Syst.},
In the present work we examine both the linear and nonlinear properties of two related parity-time (PT)-symmetric systems of the discrete nonlinear Schrodinger (dNLS) type. First, we examine the parameter range for which the finite PT-dNLS chains have real eigenvalues and PT-symmetric linear eigenstates. We develop a systematic way of analyzing the nonlinear stationary states with the implicit function theorem. Second, we consider the case when a finite PT-dNLS chain is embedded as a defect in… 
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