Ferroelectric smectic phase formed by achiral straight core mesogens.

  title={Ferroelectric smectic phase formed by achiral straight core mesogens.},
  author={Ralf Stannarius and Jianjun Li and Wolfgang Weissflog},
  journal={Physical review letters},
  volume={90 2},
We report electro-optic experiments in liquid crystalline freestanding films of achiral hockey stick shaped mesogens with a straight aromatic core. The material forms two smectic mesophases. In the higher temperature phase, a spontaneous polarization exists in the smectic layer plane and the films show polar switching in electric fields. It is the first example of a ferroelectric phase formed by nearly rodlike achiral mesogens. Mirror symmetry of the phase is spontaneously broken. We propose a… 

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