Ferroelectric modes in chiral smectic C phase

One of the most spectacular consequences of the chirality of the smectic chiral C phase, is the appearance of ferroelectricity. If the Z-axis of the laboratory frame is parallel to the helix axis, then the helical precession of the director can be described by variation of its projection on to the layer plane, = + on moving along the helix axis ( is usually referred 

Experimentally the Goldstone and soft modes exhibit properties that are unusual for dielectric process. Although both can be always well 

Precise characterization of the soft mode was thus possible because the helix can also be unwound by strong magnetic fields. This enables suppression of the Goldstone mode and uncovers the soft mode (see Fig. 4.9(b)). 

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