Publication Title

Physical Review Letters

Publication Date

2-28-2000

Document Type

Article

DOI

10.1103/PhysRevLett.84.1930

Keywords

2Nd Harmonic Generation, Ultraviolet Light, Alignment, Surface, Orientation, Monolayers, Films

Disciplines

Physics

Abstract

We observed light-induced alignment of the nematic liquid crystal, 4, 4'-n-pentylcyanobiphenyl (5CB), on a fused quartz. Irradiation of the adsorbed layer with polarized ultraviolet light produced homogeneous alignment in a 5CB-filled liquid crystal cell with the easy orientation axis perpendicular to thr polarization direction. The measured anchoring energy increases with illumination up to 10(-4) erg/cm(2). Phase retardation and pretilt measurements confirmed near homogeneous alignment of the LC in a cell, while the polarization dependence of second harmonic generation suggested a near normal alignment of the adsorbed layer. We believe that light-induced rearrangement or phototransformation of the adsorbed layer causes the observed phenomenon.

Comments

Copyright 2000 American Physical Society. Available on publisher's site at http://dx.doi.org/10.1103/PhysRevLett.84.1930.


Included in

Physics Commons

Share

COinS