Electro-Optic Characteristics of Charge-Transfer-Complex Doped Ferroelectric Liquid Crystal Device: Realization of Very High Contrast Ratio and Perfect Bistability

Abstract

Abstract A surface stabilized ferroelectric liquid crystal electro-optic device using FLC material doped with a charge-transfer-complex (CTC), TMTFF-ODTCNQ, was shown to reveal a perfect bistability yielding a 100% memory capability with an inverted polarity accompanying a high contrast ratio reaching 55:1. The relationship between the EO characteristics and the dynamics of the ions of CTC has been investigated to understand this peculiar EO performance. It was shown that the inverted bistability is caused by the formation of strong internal depolarization field originated from the ions of the CTC molecules accumulating in the interfacial region. Both the values of the depolarization field and the mobility of ions were evaluated. The value of the former was shown to reach several volts and that of the latter was 5 × 10−7 cm2/V s. These values are thought to be enough to cause the inverted bistability phenomena.