We show that the Eckhaus instability for traveling waves is of convective nature and does not directly lead to absolute instability. As a consequence spiral waves remain stable in a larger range than expected previously, transition to defect-mediated turbulence can be delayed beyond the Benjamin-Feir limit, and the occurrence of phase turbulence can be made plausible. We calculate the onset of absolute instability using the complex Ginzburg-Landau equation and verify the results by simulations.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics