The University of Southampton
University of Southampton Institutional Repository

Surface charge screening and boundary conditions for high two-beam coupling gain in pure liquid crystals

Surface charge screening and boundary conditions for high two-beam coupling gain in pure liquid crystals
Surface charge screening and boundary conditions for high two-beam coupling gain in pure liquid crystals
We report on asymmetric two-beam coupling and the ways of controlling it in liquid crystals cells with photoconducting polymer layers. The cells had one of the substrates covered with a photoconductive polymer layer, namely PVK, photosensitised with C60 to respond to visible light. Efficient gain was measured in 30 micron thick cells with two incident beams having the same intensity. We present a model of two-beam coupling gain based on the build-up and discharge of surface charge screening layers, spatially modulated due to the photoconductivity of doped PVK. The simulation of electric field distribution inside a liquid crystal cell for different two-beam coupling grating spacing showed different penetration of field into the liquid crystal bulk. The characteristics of dynamics, magnitude of two-beam coupling and the efficiency of diffraction were determined for different values of applied DC field, cell configuration and liquid crystals. We found that the direction of energy flow was determined just by the cell tilt and not by the DC field bias.
0819455741
133-140
International Society for Optical Engineering
Dyadyusha, Andriy
daa939a8-2860-4a31-ab12-7950bf59aeef
Kaczmarek, Malgosia
408ec59b-8dba-41c1-89d0-af846d1bf327
Gilchrist, Graham
3b427fc1-57c3-44a1-b3b0-4c5498b26b04
D'Alessandro, Giampaolo
bad097e1-9506-4b6e-aa56-3e67a526e83b
Parka, Janusz
7d30bbbb-2777-41a5-a390-91a03b354a9f
Dabrowski, Roman S.
e48eb4f8-128c-4a2e-b35e-24ee8eacc33a
Vere, Anthony W.
Grote, James G.
Kajzar, Francois
Dyadyusha, Andriy
daa939a8-2860-4a31-ab12-7950bf59aeef
Kaczmarek, Malgosia
408ec59b-8dba-41c1-89d0-af846d1bf327
Gilchrist, Graham
3b427fc1-57c3-44a1-b3b0-4c5498b26b04
D'Alessandro, Giampaolo
bad097e1-9506-4b6e-aa56-3e67a526e83b
Parka, Janusz
7d30bbbb-2777-41a5-a390-91a03b354a9f
Dabrowski, Roman S.
e48eb4f8-128c-4a2e-b35e-24ee8eacc33a
Vere, Anthony W.
Grote, James G.
Kajzar, Francois

Dyadyusha, Andriy, Kaczmarek, Malgosia, Gilchrist, Graham, D'Alessandro, Giampaolo, Parka, Janusz and Dabrowski, Roman S. (2004) Surface charge screening and boundary conditions for high two-beam coupling gain in pure liquid crystals. Vere, Anthony W., Grote, James G. and Kajzar, Francois (eds.) In Optical Materials in Defence Systems Technology. vol. 5621, International Society for Optical Engineering. pp. 133-140 . (doi:10.1117/12.578530).

Record type: Conference or Workshop Item (Paper)

Abstract

We report on asymmetric two-beam coupling and the ways of controlling it in liquid crystals cells with photoconducting polymer layers. The cells had one of the substrates covered with a photoconductive polymer layer, namely PVK, photosensitised with C60 to respond to visible light. Efficient gain was measured in 30 micron thick cells with two incident beams having the same intensity. We present a model of two-beam coupling gain based on the build-up and discharge of surface charge screening layers, spatially modulated due to the photoconductivity of doped PVK. The simulation of electric field distribution inside a liquid crystal cell for different two-beam coupling grating spacing showed different penetration of field into the liquid crystal bulk. The characteristics of dynamics, magnitude of two-beam coupling and the efficiency of diffraction were determined for different values of applied DC field, cell configuration and liquid crystals. We found that the direction of energy flow was determined just by the cell tilt and not by the DC field bias.

Full text not available from this repository.

More information

Published date: 2004
Venue - Dates: Optical Materials in Defence Systems Technology, 2004-10-25 - 2004-10-27

Identifiers

Local EPrints ID: 15124
URI: https://eprints.soton.ac.uk/id/eprint/15124
ISBN: 0819455741
PURE UUID: 8c1fe678-5915-4f50-865c-a1bd97d935ee
ORCID for Giampaolo D'Alessandro: ORCID iD orcid.org/0000-0001-9166-9356

Catalogue record

Date deposited: 17 Mar 2005
Last modified: 06 Jun 2018 13:05

Export record

Altmetrics

Contributors

Author: Andriy Dyadyusha
Author: Graham Gilchrist
Author: Janusz Parka
Author: Roman S. Dabrowski
Editor: Anthony W. Vere
Editor: James G. Grote
Editor: Francois Kajzar

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×