Suppressing acceleration of 2D Airy beams in Lieb photonic lattices with saturable nonlinear media

We analyze the evolution of transverse acceleration two-dimensional (2D) Airy beams propagating in Lieb photonic lattices with different photorefractive self-focusing nonlinearity. Numerical simulation shows that a decreased transverse acceleration of Airy beam and even a completely stopped state, the energy localized at the main lobe position, can be reached while the Airy beam is launched into the on-site/off-site of the Lieb photonic lattices by varying the medium nonlinearity. We discover that the transverse acceleration when the main lobe of Airy beam incident to off-site of the Lieb photonic lattice can be suppressed, which need a bias voltage larger than the on-site case when the main lobe of Airy beam incident to off-site of the Lieb photonic lattice. Additionally, the main lobe energy of the Airy beam still converges at the attractive defect lattice sites and spreads out to surrounding lattice sites due to the existence of repulsive defects under saturable nonlinearity.