Light in a twist: optical angular momentum
Presented by Prof. Miles PADGETT on 9 Jul 2014 from 09:00 to 10:00
Type: Oral Presentation
Track: Track H - Plenaries
In 1992 Allen et al. recognized that light beams carrying an orbital angular momentum, in addition to the photon spin, could be created in the laboratory. This twist can be generated using lenses, or holograms encoded onto liquid crystal displays. Both whole beams and single photons can carry this twist, or transfer it to particles causing them to spin. In this talk I will introduce the underlying properties and discuss a number of manifestations of orbital angular momentum. These various demonstrations by our own group and others highlight how optics still contains surprises and opportunities for micro-manipulation, novel imaging modalities and high bandwidth communication in both the classical and quantum worlds. Our most recent work considers how a rotational form of the classical Doppler effect might by used to sense the rotation of distant bodies, even when the linear effect is zero.