Quantitative definition of patterns in soft-mode turbulence suppressing the Nambu-Goldstone mode.
ABSTRACT Chaotic patterns in electroconvection of homeotropic nematics, soft-mode turbulence (SMT), and the related spatiotemporal chaos (STC) are discussed, and the quantitative definition of the patterns is considered. The order parameter S, obtained directly from the 2D spectra of the patterns, is introduced. The contribution of the Nambu-Goldstone mode and the increase in pattern regularity under the influence of an external magnetic field H are evaluated. We propose a schematic phase diagram of STC patterns based on the value of S.