  We demonstrate an exceptional ability of a high-polarisation 3D ferroelectric
liquid to form freely-suspended fluid fibres at room temperature. Unlike fluid
threads in modulated smectics and columnar phases, where translational order is
a prerequisite for forming liquid fibres, recently discovered ferroelectric
nematic forms fibres with solely orientational molecular order. Additional
stabilisation mechanisms based on the polar nature of the mesophase are
required for this. We propose a model for such a mechanism and show that these
fibres demonstrate an exceptional non-linear optical response and exhibit
electric field-driven instabilities.
