| Summary: | A small quantity of hexagonal boron nitride (<i>h</i>-BN) flakes is doped into a nematic liquid crystal (LC). The epitaxial interaction between the LC molecules and the <i>h</i>-BN flakes rising from the <i>π</i>−<i>π</i> electron stacking between the LC’s benzene rings and the <i>h</i>-BN’s honeycomb structure stabilizes pseudo-nematic domains surrounding the <i>h</i>-BN flakes. Electric field-dependent dielectric studies reveal that the LC-jacketed <i>h</i>-BN flakes follow the nematic director reorientation upon increasing the applied electric field. These anisotropic pseudo-nematic domains exist in the isotropic phase of the LC+<i>h</i>-BN system as well, and interact with the external electric field, giving rise to a nonzero dielectric anisotropy in the isotropic phase. Further investigations reveal that the presence of the <i>h</i>-BN flakes at a low concentration in the nematic LC enhances the elastic constants, reduces the rotation viscosity, and lowers the pre-tilt angle of the LC. However, the Fréedericksz threshold voltage stays mostly unaffected in the presence of the <i>h</i>-BN flakes. Additional studies show that the presence of the <i>h</i>-BN flakes enhances the effective polar anchoring strength in the cell. The enhanced polar anchoring strength and the reduced rotational viscosity result in faster electro-optic switching in the <i>h</i>-BN-doped LC cell.
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