Directed percolation criticality in turbulent liquid crystals

Area of Science:

• Physics
• Soft Matter Physics
• Fluid Dynamics

Background:

• Electrohydrodynamic convection in nematic liquid crystals exhibits complex turbulent states.
• Understanding phase transitions in nonequilibrium systems is a significant challenge in statistical physics.

Purpose of the Study:

• To experimentally investigate the critical behavior of phase transitions between different turbulent states in electrohydrodynamic convection.
• To determine the universality class of these transitions and provide experimental evidence for theoretical models.

Main Methods:

• Experimental investigation of electrohydrodynamic convection in nematic liquid crystals.
• Statistical analysis of spatiotemporal intermittency regimes.
• Determination of static critical exponents.

Main Results:

• Observed critical behavior consistent with the directed percolation universality class in 2+1 dimensions.
• Detailed characterization of spatiotemporal intermittency regimes.
• Complete set of static critical exponents were determined.

Conclusions:

• The study provides the first clear and comprehensive experimental evidence of an absorbing phase transition in this system.
• The findings confirm the applicability of the directed percolation universality class to nonequilibrium phenomena in liquid crystals.
• This research advances the understanding of critical phenomena in complex fluid systems.