Nonlinear Beam Propagation in a Class of Complex Non-PT -Symmetric Potentials

Abstract

The subject of PT -symmetry and its areas of application have been blossoming over the past decade. Here, we consider a nonlinear Schrödinger model with a complex potential that can be tuned controllably away from being PT - symmetric, as it might be the case in realistic applications. We utilize two parameters: the first one breaks PT -symmetry but retains a proportionality between the imaginary and the derivative of the real part of the potential; the second one, detunes from this latter proportionality. It is shown that the departure of the potential from the PT -symmetric form does not allow for the numerical identification of exact stationary solutions. Nevertheless, it is of crucial importance to consider the dynamical evolution of initial beam profiles. In that light, we define a suitable notion of optimization and find that even for non PT -symmetric cases, the beam dynamics, both in 1D and 2D –although prone to weak growth or decay– suggests that the optimized profiles do not change significantly under propagation for specific parameter regimes.