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Successful alignment control of the B4 helical nanofilament assembly in a binary mixture system of bent‐shaped and rod‐shaped liquid crystals is demonstrated. The aligned nanofilament domains appear as extremely smooth and uniform stripes over millimeters. The interferometric second‐harmonic generation microscopy technique is developed and applied to these aligned domains. It is found that not only chirality, but also polarity, are preserved in a single domain formed from a single nucleus. Such an easily processed uniform bulk of the spontaneously symmetry‐broken material is intriguing in functional materials science.

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Smectic layer orientation was investigated for the side-chain PM10ME liquid crystal polymer to which steady shear and large amplitude oscillatory shear (LAOS) flows were applied. Two types of orientation are achieved depending on the shear rate γ̇ and the frequency ω, both of which are presumed to be inversely proportional to the time scale of shear flow. Parallel orientation with the layer normal in the velocity gradient direction is achieved by steady shear flow at γ̇ < 10−1 s−1, but the layers undulate along the neutral direction. Undulation is eliminated under LAOS flow at ω > 101 rad s−1, which gives a transparent sample with perfect parallel orientation. Shear flows under other conditions (steady shear at γ̇ > 10−1 s−1 and LAOS at ω < 101 rad s−1) tend to induce perpendicular orientation in which the layer normal points in the neutral direction. These results show that layer orientation changes from parallel to perpendicular and back to parallel with shortening time scale of shear flow. These changes in orientation are explainable if fluctuations, which couple to shear flow to induce perpendicular orientation, are averaged out and suppressed under the longer- and shorter-time scale shear flows.

On page 2701, Fumito Araoka and co-workers report that successful alignment of the B4 helical nanofi lament assembly is possible in a binary mixture system of bent-and rod-shaped liquid crystals. The aligned nanofi lament domains appear as extremely smooth and uniform stripes over millimeters. Second-harmonic generation (SHG) studies, including a new technique called interferometric SHG microscopy, reveal that in these aligned domains, both polarity from the nucleus and chirality are preserved.