
14.1. SELF-FOCUSING AND SOLITONS IN LIQUID CRYSTALS 477
experiments [6, 7]. When the external electric field E is applied along the x axis, the
reorientation dynamics is described by the following equation [2]"
1
1
2
sin(20) + ~ eon21A[ 2 sin(20) = 0,
KV20 + :AeRFE
2
(14.1.4)
where A~RF is the low-frequency anisotropy.
Two-dimensional self-focusing of a light beam in bulk nematics has been observed
using both capillaries and planar cells. In one set of experiments [4, 5], the nematic
liquid crystal was inserted in a glass capillary with an inner diameter of 1.5 mm. The
optical beam from an argon laser was focused