Vortex knots in light

Abstract

Optical vortices generically arise when optical beams are combined. Recently,\nwe reported how several laser beams containing optical vortices could be\ncombined to form optical vortex loops, links and knots embedded in a light beam\n(Leach et al 2004). Here, we describe in detail the experiments in which vortex\nloops form these structures. The experimental construction follows a\ntheoretical model originally proposed by Berry and Dennis, and the beams are\nsynthesised using a programmable spatial light modulator and imaged using a CCD\ncamera.\n