AC-field–enhanced beam coupling in photorefractive, hybrid liquid crystals
School of Physics and Astronomy, Southampton University - University Road, Highfield, Southampton, Hampshire, SO17 1BJ, UK, EU
2 School of Mathematics, Southampton University - University Road, Highfield, Southampton, Hampshire, SO17 1BJ, UK, EU
Accepted: 23 May 2011
The use of photorefractive layers in liquid crystal cells to achieve beam coupling typically requires an applied DC field to achieve high gain. In hybrid cells, with PVK:C60 polymer sandwiched with nematic liquid crystals, this limitation can be lifted by using a low-frequency AC field. AC fields with frequencies between 1 and 10 Hz lead to gain values that are larger than those at equivalent DC fields. The optical response of the hybrid liquid crystal system to the AC field can be understood using a simple impedance ladder model.
PACS: 42.65.Hw – Phase conjugation; photorefractive and Kerr effects / 42.70.Df – Liquid crystals / 42.79.Kr – Display devices, liquid-crystal devices
© EPLA, 2011