Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• beam nanopatterning; nematic liquid crystal; optical retardation; pretilt control; surface anchoring; Introduction Liquid crystal (LC) interactions with adjacent interfaces play a key role in LC-based optical devices as they are responsible for stabilizing mono-domain LC configurations and ensuring

• colour variation is clearly seen in thinner cells depicted in Figure 2a–c. For the thicker cell shown in Figure 2d, one should take into account that the optical retardation of the background roughly equals 4π, and above the patterned areas the retardation grows from zero (above the bottom broad stripe

• thickness values: 3.8 μm (a), 5.0 μm (b), 6.5 μm (c) and 13 μm (d) (a) The relative optical retardation (a) measured at a wavelength of 546 nm, and the pretilt angle (b) as functions of the duty factor for the nematic LC layers of different thickness d above the areas patterned with different periodicity P

Nematic liquid crystal alignment on subwavelength metal gratings

• Irina V. Kasyanova,
• Artur R. Geivandov,
• Vladimir V. Artemov,
• Maxim V. Gorkunov and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 42–47, doi:10.3762/bjnano.9.6

• formed within one grating (Figure 3b), which points out the difference in optical retardation and the LC alignment. When the polarizer axes are parallel (Figure 3c), the reference squares and gratings are bright and the gratings are dark. In the crossed polarizers with the sample axis perpendicular to

Study of the vertically aligned in-plane switching liquid crystal mode in microscale periodic electric fields

• Artur R. Geivandov,
• Mikhail I. Barnik,
• Irina V. Kasyanova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 11–19, doi:10.3762/bjnano.9.2

• 1957/5 and exhibits almost double birefringence (∆n). The larger birefringence of E7 allows for making smaller cells with an equivalent optical retardation. Also, the larger low-frequency dielectric anisotropy of E7 yields a stronger electric field torque, which is favorable for shortening the