Electro-hydrodynamic programming reshapes liquid crystal dynamics in free-form director fields

Abstract

This study unveils a groundbreaking technique leveraging the superposition of electric field vectors to manipulate liquid crystals (LCs). Demonstrated through a simple configuration of four independent electrodes at the corners of a rectangular enclosure, notably, this configuration can be further simplified or modified as needed, showcasing the versatility of the approach. Significantly, the design showcased in the paper eliminates the need for an alignment layer, highlighting the versatility of the method. Through nuanced adjustments in waveforms, amplitudes, frequencies, and phases in AC or DC from these electrodes, precise control over LC shape deformation and dynamic phase transformation is achieved in both temporal and spatial dimensions. In contrast to traditional methods, the approach presented here abolishes alignment layers and intricate electrode-array systems, opting for a streamlined configuration with varying AC frequencies and DC electric signals. This innovative methodology, founded on simplified governing equations from Q-tensor hydrodynamics theory, demonstrates true 3D control over LCs, displaying efficiency in electrode usage beyond current arrays. The study's contributions extend to temporal control emphasis, superposition techniques, and the elimination of fixed electrodes, promising unprecedented possibilities for programming LC materials and advancing the field of programmable LC devices.