Real-time dynamic hologram in photorefractive ferroelectric liquid crystal with two-beam coupling gain coefficient of over 800 cm–1 and response time of 8 ms

Abstract

The photorefractive effect in photoconductive ferroelectric liquid crystals (FLCs) that contain photoconductive chiral compounds was investigated. Terthiophene compounds with chiral structure were chosen as the photoconductive chiral compounds and mixed with an achiral smectic C liquid crystal. The mixture exhibited the ferroelectric chiral smectic C phase and photoconductivity. The photorefractivity of the mixture was investigated by two-beam coupling experiment. It was found that the FLC containing the photoconductive chiral compound exhibits a large gain coefficient of over 800 cm−1 and a fast response time of 8 ms. The high photorefractive performance was considered to be due to enhanced charge mobility.

Dynamic Amplification of Optical Signals in Photorefractive Ferroelectric Liquid Crystals

“…2(b)]. This phenomenon where one beam is amplified by another beam is termed asymmetric energy exchange in a two-beam coupling experiment [1,2]. The photorefractivity of a material is confirmed by the occurrence of this asymmetric energy exchange, which has the potential for a vast variety of optical applications.…”

“…The photorefractive effect is a phenomenon that allows for the formation of holographic images within a material; it provides the potential to realize dynamic holograms by recording holograms as a change in the refractive index of a medium [1,2]. The characteristic phenomenon of the photorefractive effect is asymmetric energy exchange in two-beam coupling that can be used to coherently amplify signal beams; therefore, the photorefractive effect has the potential to be used in a wide range of optical technologies similar to a transistor in electrical circuits.…”

Liquid crystals: applications and industry

“…They are essentially stereoscopic rather than holographic, using clever optical tricks to send two different images to the eyes rather than actually producing a threedimensional image. However, researchers at the Tokyo University of Science have demonstrated a device using a doped ferroelectric liquid crystal that could hope to change this [4].…”

Современное Состояние Разработки Светочувствительных Сред Для Голографии (Обзор)

“…Оказалось, что такие слои проявляют фотомеханический эффект. Исследование свойств ферроэлектрических ЖК LV−LVII, содержащих в своем составе, кроме фотосенсибилизатора LVIII, фотопроводящее хиральное соединение LIX, показало, что при регистрации голограмм с η = 1−2% лазерным излучением с λ = 488 nm при наложении электрического напряжения до 2 V/µm наблюдался значительный фоторефрактивный эффект, обеспечивающий визуализацию голограмм за 8 ms [172]. Это открывает возможность создания динамических 3D дисплеев, работающих в реальном масштабе времени.…”