Mixtures of two proprietary low molar mass organosiloxane liquid crystals were studied in order to improve their alignment and optimize their electro-optic properties for telecommunication applications. Over a certain concentration range, mixtures exhibited an isotropic–chiral smectic A–chiral smectic C (Iso–SmA*–SmC*) phase sequence leading to exceptionally good alignment. At room temperature, the spontaneous polarization of these samples was reduced from 225 nC cm<sup>-2</sup> in the pure SmC* liquid crystal to as low as 75 nC cm<sup>-2</sup> in the mixture. Within this concentration range, the ferroelectric tilt angle could be varied between 35° and 15°, while the rise time decreased by 69.4%. The rise times were < 45 <i>μ</i>s for moderate electric fields of ±10 V<i>μ</i>m<sup>-1</sup> in the SmC* phase and ~4 <i>μ</i>s, independent of electric field, in the SmA* phase. At λ = 1550 nm, these mixtures exhibited very large extinction ratios of ~60 dB for binary switching in the SmC* phase and ~55 dB continuous variable attenuation in the SmA* phase.
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