Nonlinear optical recording in a ferroelectric nematic liquid crystal with a giant dipole moment

We report on highly efficient dynamic holographic recording in a multicomponent ferroelectric nematic liquid crystal mixture. Polarizing optical microscopy revealed that the texture strongly depends on boundary conditions and on the time elapsed since filling. Upon application of a DC electric field, the initial polydomain structure was disrupted; after removal of the field, the sample relaxed into a uniform monodomain state within several hours. Once established, this ordered state was found to be stable and reproducible, persisting through subsequent electric-field cycles and thermal transitions to the isotropic phase. Nonlinear optical measurements demonstrated that the stabilized NF phase supports the recording of light-induced diffraction gratings with dynamic diffraction efficiencies of up to 20%, which were fully reversible and controllable by applied voltage. The results confirm that ferroelectric nematic liquid crystals combine spontaneous polarization, fluidity, and strong optical nonlinearity, highlighting their potential for tunable dynamic holography, adaptive photonics, and non-volatile optical data storage.