Liquid Crystalline Blue Phases - Liquid Crystalline Functional Assemblies and Their Supramolecular Structures - page 111

Fig. 12 Chemical structure of T-shaped dimeric liquid crystal molecules that broadened
the temperature range of blue phases to 13 K [24]
Fig. 13 Chemical structure of materials exhibiting a blue phase with a wide temperature
range [25]
ity was suggested to stabilize the disclination. This system is very interesting
with respect to potential application, since the diffraction wavelengths of the
blue-phase lattice can be changed reversibly by applying an electric field.
A theoretical approach for stabilizing the blue phases has been investigated
within the framework of Landau-de Gennes theory [26].
Technologies to expand the narrow temperature range of blue phases have
thus been in rapid development in recent years. At last, it seems that we have
arrived at the dawn of an era in which real progress will be made towards
realizing practical applications of blue phases.
8
Smectic Blue Phase
New chiral phases, called smectic blue phases (BPSm), have been discov-
ered in a small temperature range with the following phase sequence: TGB-
BP Sm 1-BP Sm 2-BP Sm 3-Iso, without any intermediate chiral nematic phase be-
tween the BPSm and TGB phases [27, 28]. X-ray scattering studies showed
that unlike the traditional blue phases, the smectic blue phases possess the
quasi-long-range smectic order in addition to three-dimensional orienta-