Optical turbulence control by non-Hermitian potentials

Abstract

We propose a method for a control of turbulence by modifying the excitation cascade leading to turbulence. The method is based on the asymmetric coupling between the spatiotemporal excitation modes by non-Hermitian potentials. The non-Hermitian potentials are recently known to enable unidirectional coupling between modes. We demonstrate that such unidirectional coupling towards larger (smaller) wave numbers can increase (reduce) the energy flow in turbulent states, and therefore, influence the character of turbulence. The study is based on the complex Ginzburg-Landau equation, a universal model for pattern formation and turbulence in a wide range of systems including nonlinear optical resonators. We show that enhancement or reduction of turbulence is indeed dependent on the imposed direction of the energy flow, controlled by the phase shift between the real and imaginary parts of the temporal oscillation of the non-Hermitian potential.