Liquid Crystals. Iam-Choon Khoo
rel="nofollow" href="#ulink_4d0c73c7-2dcd-5fc9-8a77-f6bed50c14af">Figure 2.1. Coordinate system defining the microscopic order parameter of a ...Figure 2.2. Schematic depiction of the numerical solution of the two transce...Figure 2.3. (a) Observed oscilloscope trace of the diffracted signal in a dy...Figure 2.4. Observed buildup times of the diffracted signal associated with ...Figure 2.5. Schematic depiction of the molecular levels involved in ground e...Figure 2.6. Free energies F(Q) for different temperatures T. At T = Tc, ∂
3 Chapter 3Figure 3.1. (a) Twist deformation in a nematic liquid crystal; (b) splay def...Figure 3.2. A homeotropic nematic liquid crystal with strong surface anchori...Figure 3.3. Soft‐boundary condition. The applied field will reorient both th...Figure 3.4. Dispersion data of the dielectric constant ε|| and ε Figure 3.5. Dispersion data of the dielectric constant ε|| and ε Figure 3.6. Measured birefringence De = ε|| − ε⊥ of three ...Figure 3.7. (a) Temperature dependence of the refractive indices of 5CB in t...Figure 3.8. Plot of dn||/dT and dn⊥/dT for the liquid crystal for te...Figure 3.9. An elementary volume of fluid moving at velocity v (r, t) in spa...Figure 3.10. Stresses acting on opposite planes of an elementary volume of f...Figure 3.11. Sheer flow in the presence of an applied magnetic field.Figure 3.12. Pure twist deformation induced by an external magnetic field H ...Figure 3.13. Director axis reorientation causing flows.
4 Chapter 4Figure 4.1. (a) Helical arrangement of the director axis in a cholesteric li...Figure 4.2. Field‐induced untwisting of a cholesteric liquid crystal: (a) id...Figure 4.3. Reflection and transmission of circularly polarized light in a c...Figure 4.4. (a) Relation between frequency (ωr) and wave vector (l) ...Figure 4.5. Replot of Figure 4.1(a) by distinguishing the different polariza...Figure 4.6. Different branches of ωr – k relation for a cholesteric ...Figure 4.7. The value of (b − a)/(b + a) for different branches.Figure 4.8. (a) Transmission of randomly polarized light (containing right‐ ...Figure 4.9. (a) Numerical calculated photonic band structure for axial propa...Figure 4.10. Photonic band structure for RCP eigenmode near band edge kz ...Figure 4.11. Dispersion relationship near the band‐edge for cholesteric liqu...Figure 4.12. Schematic of polarization rotation of a linearly polarized ligh...Figure 4.13. (a) Plot of transmission T, polarization figure‐of‐merit (PF), ...Figure 4.14. Vector laser beams with (left) radial polarization and (right) ...Figure 4.15. Time evolution of the PBG shift associated with crystalline def...Figure 4.16. (a) A smectic‐A liquid crystal. (b) A liquid crystal that exhib...Figure 4.17. Splay distortion in a SmA liquid crystal.Figure 4.18. Measured values of bend and splay elastic constant in the nemat...Figure 4.19. Directions of the applied field components of H relative to the...Figure 4.20. Rotation of the C axis around the layer normal; no change in la...Figure 4.21. A helically modulated smectic‐C* liquid crystal, the directions...
5 Chapter 5Figure 5.1 Scattering of light from an elementary volume located at r.Figure 5.2. Coordinate system for analyzing light scattering in NLCs in term...Figure 5.3. Geometries for an intense scattering of the incident light. Note...Figure 5.4. Photograph of the transmitted laser beam through a NLC film (100...Figure 5.5. Experimentally measured scattering loss in a NLC (E46) that is h...Figure 5.6. Raman scattering involving the generation of Stokes and anti‐Sto...Figure 5.7. A typical spectrum of light spontaneously scattered from a liqui...Figure 5.8. Wave vector addition rule for the Brillouin scattering processes...Figure 5.9. Typical laser‐nematic director axis interaction geometry in a wa...
6 Chapter 6Figure 6.1. Schematic of a typical liquid crystal display pixel consisting o...Figure 6.2. Index ellipsoid for a plane‐polarized optical wave propagating a...Figure 6.3. Typical electro‐optic modulation scheme with polarizer–analyzer ...Figure 6.4. Various states of polarization resulting from the addition of tw...Figure 6.5. Capacitance measurements of an undoped 5CB and a CdSe‐doped 5CB ...Figure 6.6. Applied electric field‐director axis interaction geometry for (a...Figure 6.7. Director axis reorientation profile in the cell at various appli...Figure 6.8. Tilting and unwinding of the director axis of a 90° twisted NLC ...Figure 6.9. Light propagating through an initially homeotropic LC cell. The ...Figure 6.10. Schematic of a ferroelectric liquid crystal light switch with p...Figure 6.11. A SMFLC switching set‐up.Figure 6.12. Schematic of the various components of a typical OALCSLM operat...Figure 6.13. Non‐close‐packed inverse opal photonic crystal structure.Figure 6.14. Electrical tuning of Bragg reflection peak of NLC filled non‐cl...Figure 6.15. (a) Unit cell of an all‐dielectric polarization‐independent FSS...Figure 6.16. Transmission spectra of an all‐dielectric FSS with a liquid cry...Figure 6.17. Schematic depiction of aligned liquid crystal for chemical sens...
7 Chapter 7Figure 7.1. Paired metallic nanorods that exhibits negative index of refract...Figure 7.2. (a) A planar aligned nematic liquid crystal containing core‐shel...Figure 7.3. Illustration of a plane light wave propagating along z‐axis thro...Figure 7.4. Index ellipsoid for a uniaxial medium such as nematic liquid cry...Figure 7.5. Propagation of a polarized light through a birefringent phase pl...Figure 7.6. Schematic depiction of a pixel element that consists of an input...Figure 7.7. The N + 1 layers representation of an LC cell between polarizers...
8 Chapter 8Figure 8.1. Laser‐induced molecular alignment along the direction of the opt...Figure 8.2. Interaction of a linearly polarized light with an anisotropic (b...Figure 8.3. Observed dependence of the orientation relaxation time as a func...Figure 8.4. Measured optical nonlinear susceptibility as a function of the t...Figure 8.5. Schematic of the interaction geometry involving a linearly polar...Figure 8.6. Schematic depiction of the director axis reorientation profile i...Figure 8.7. (a) Plot of ωθ/ω0 as a function of ω0/dFigure 8.8. Schematic diagram of the optical fields and their propagation di...Figure 8.9. Typical observed temperature dependence (dots) of the nonlinear ...Figure 8.10. (Top) Molecular structures of a commercial dye DR1, MR dye, and...Figure 8.11. Schematic depiction of the surface and bulk space‐charge field ...Figure 8.12. Schematic depiction of the optical wave mixing configuration to...Figure 8.13. (a) Typical dependence of the PR self‐diffraction efficiency on...Figure 8.14. Smectic‐C liquid crystal axis azimuthal rotation by an external...Figure 8.15. “Bookshelf‐like” configuration of a ferroelectric liquid crysta...
9 Chapter 9Figure 9.1. Absorption spectra of four liquid crystals.Figure 9.2. (a) Single‐photon absorption process; (b) two‐photon absorption ...Figure 9.3. (a) Molecules are pulled toward regions of higher field strength...Figure 9.4. Schematic depiction of the radial components of the Maxwell stre...Figure 9.5. Experimental setup for probing the dynamics of laser‐induced tra...Figure 9.6. Interference of the propagative index gratings (arising from ele...Figure 9.7. Oscilloscope trace of the observed probe diffraction evolution w...Figure 9.8.