Superlattice patterns and spatial instability induced by delay feedback.

摘要: Various oscillatory superlattice patterns in a reaction–diffusion system are observed by means of delay feedback (DF) the parametric domain where without DF displays uniform bulk oscillation. By varying parameters within an appropriate range, undergoes transitions to hexagons, stripes and squares, square superlattices with different wavenumbers also obtained. Linear stability analysis reveals that do not result from Turing instability possible mechanism pattern formation is suggested proved analytically: induces homogeneous limit cycle respect spatial perturbations even if does occur, so possessing corresponding modes produced. The behavior dominant characteristic multiplier seems be connected selection. Here it clearly demonstrated can play destabilizing role spatially extended instead stabilizing periodic orbits or turbulent states, which most earlier works have usually focused on.