  Direct viscous mechano-electric response is demonstrated for a
room-temperature ferroelectric nematic liquid, which combines large spontaneous
electric polarization with 3D fluidity. The mechano-electric transduction is
observed in the frequency range 1-200 Hz via a simple demonstrator device. The
liquid is placed into a deformable container with electrodes and the electric
current induced by both periodic and irregular actuation of the container is
examined. The experiments reveal a rich interplay of several distinct viscous
mechano-electric phenomena, where both shape deformations and material flow
cause changes in the electric polarization structure of a ferroelectric nematic
liquid. The results show that the mechano-electric features of the material
promise a considerable applicative perspective spanning from sensitive tactile
sensors to energy harvesting devices.
