Figure 1

(a) Bookshelf smectic liquid crystal cell geometry. The tilted chiral liquid crystal is a dielectric in a transparent ITO-glass capacitor, with the smectic layers more or less normal to the plates. Shown are the director $\mathbf{n}$, the tilt cone angle $\theta$ relative to the layer normal $\mathbf{z}$, the polarization $\mathbf{P}$, the $\mathbf{c}$ director (the projection of $\mathbf{n}$ onto the layer plane), the azimuthal orientation $\varphi$ of $\mathbf{c}$-$\mathbf{P}$, and the cell normal $\mathbf{x}$. The cells have total thickness $d$, with alignment layers of thickness $t$ on each surface. (b)–(d) Model structures of Sm-$C^{*}$ SSFLC cells with $\mathbf{c}$ indicated by $⊣$ and $\mathbf{P}$ by $\to$. (b) Twisted structure resulting from strong polar surface anchoring. The resulting splay in the polarization causes a polarization charge density, and thus a nonzero electric field, within the cell. (c) Large $\mathbf{P}$ excludes splay from the cell interior, reducing the electrostatic energy at the cost of elastic energy. (d) With insulating alignment layers present, polarization screening excludes the electric field from the LC and the applied voltage is dropped entirely across the alignment layers.Reuse & Permissions

Figure 2

(a) Contour plot of the transmitted intensity $T(\alpha ,V)$ of $632\mathrm{n}\mathrm{m}$ light through a bookshelf-aligned W415 cell placed between crossed polarizers, as a function of increasing applied voltage and of azimuthal orientation. Right axis: Apparent bulk director orientation ${\psi }_B$ relative to $\mathbf{n}$, determined from the minima of $T(\alpha )$. Inset: Setup for TIR study of the LC orientation near the glass surface via depolarization of the reflected He-Ne beam. The beam along the hemisphere axis probes the director field of the bulk LC. (b) Contour plot of the corresponding depolarized TIR intensity $R(\alpha ,V)$. Right axis: Apparent surface director orientation ${\psi }_S$ relative to $\mathbf{n}$, determined from the minima of $R(\alpha )$. Inset, hysteresis loop: Apparent bulk and surface director orientation dependence on applied voltage. Inset, line: ${\psi }_S$ vs ${\psi }_B$. The cell was driven with a $20\mathrm{H}\mathrm{z}$, $20{\mathrm{V}}_{pp}$ triangle wave.Reuse & Permissions

Figure 3

(a) $V_{\mathrm{s}\mathrm{a}\mathrm{t}}$ measured as a function of total alignment layer thickness. The solid line is the best fit to the data. (b) $V_{\mathrm{s}\mathrm{a}\mathrm{t}}$ measured as a function of total cell thickness.Reuse & Permissions