Splaying and Bending in Ferroelectric Nematic Liquid Crystals

Ferroelectric order in liquids represents a fundamental challenge in condensed matter physics. The discovery of the ferroelectric nematic (N_F) phase marked a turning point, leading to the discovery of a broader “ferroelectric nematic realm” encompassing diverse polar mesophases, such as SmA_F, SmC_F, or the polar heliconical nematic (N_TBF) and heliconical smectic (SmC_PH) phases, combining ferroelectric order with spontaneous chiral symmetry breaking. Here, I will initially comment on the notable nonlinear optical properties, which offer promising avenues for photonic applications. Then, I will discuss our latest results on how splay and bend fluctuations govern phase transitions.