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Figure 1.  Molecular structures of (a) CCN47 and (b) 8CB. Arrows indicate the direction of permanent dipoles.

Figure 2.  (a) The phase diagram of various mixtures. Cr, SmA, N, and Iso represent the crystalline phase, smectic A phase, nematic phase, and isotropic phase, respectively. (b) POM images of C₁₀ in isotropic, nematic, smectic A, and crystalline phases under crossed polarizers without and with a full-wave plate. The rubbing direction R is indicated by the double arrows.

Figure 3.  The principle schematics of dielectric permittivity verifying with frequency. (a) Measurement of C_filled for ε_⊥, (b) measurement of C_filled for ε_∥.

Figure 4.  The dielectric permittivity ε_∥ and ε_⊥ of (a) C₂₀ in 20 °C, (b) C₇₀ in 20 °C, (c) C₈₀ in 20 °C, (d) C₂₀ in −10 °C and (e) C₁₀ in −6 °C, (f) Δε corresponding to panels (a)–(e).

Figure 5.  The change of dielectric permittivity and dielectric anisotropy from 60 °C to −40 °C in (a) C₂₀, (b) C₆₀, and (c) C₉₀. (d) The maximum and minimum of Δε in different mixtures. All the frequency of output signal is fixed on 20 kHz.

Figure 6.  (a) The relationship between dielectric anisotropy and the concentration of CCN47 at the frequency of 20 kHz and the temperature of 5 °C below T_NI. Δε of the mixtures with different concentrations of CCN47 at the temperature of (b) 10 °C, (c) 20 °C, and (d) 30 °C below T_NI, and the frequency is varied from 20 Hz to 1 MHz.

Figure 7.  (a) The temperature range of dual-frequency characteristics for the LCs mixtures with different mass ratios of CCN47. (b) The minimum and maximum of Δε in mixtures with different mass ratios of CCN47 at different temperatures. Red represents Δε > 0, white represents Δε = 0, and blue represents Δε < 0.