H. Xu, P.G. Kevrekidis, and D.E. Pelinovsky
Existence and stability of PT-symmetric states in nonlinear two-dimensional square lattices
Physica D 326 (2016), 1-20
Vortices symmetric with respect to simultaneous parity and time reversing transformations
are considered on the square lattice in the framework of the discrete nonlinear Schrodinger
equation. The existence and stability of vortex configurations is analyzed in the limit
of weak coupling between the lattice sites, when predictions on the elementary cell of a square
lattice (i.e., a single square) can be extended to a large (yet finite) array of lattice cells.
Our analytical predictions are found to be in good agreement with numerical computations.
discrete nonlinear Schrodinger equation, vortices, existence and stability,
parity-time reversal symmetry, anti-continuum limit.