Vortices embedded in a laser beam have been transferred
to cold atoms so that researchers can study how circulation
currents persist in the form of coherent matter waves.
improving our understanding of wave
phenomena. A wide range of basic,
challenging questions about the intricate
manifestations and interactions of vortices await solutions. t
With current spatial light modulator
technologies, such as liquid crystal on
silicon, shaping a beam into an arbitrary
profile can be readily done with high
efficiency and accuracy. Non-diffracting
beams have so far found applications in
optical interconnects, where they can
activate photodetector-based switches in
series, even within the same line of view,
since the configuration of their angular
spectrum also allows for the reconstruction of the beam after it has been partially blocked by an opaque object.
More recently, Mathieu beams have
also been used as optical lattices for the
propagation of solitons in nonlinear
media. Since the intensity is modulated
along elliptical rings, this approach
allows for the tuning of the rotational
velocity in solitons trapped in a lattice
with this geometry.
The study of optical vortices constitutes an under-explored gateway to
Visit OPN online ( www.osa-opn.org) to view
a slideshow of beautiful images of naturally
occurring vortices.
Carlos López-Mariscal ( clopez@nist.gov) is
with the National Institute of Standards and
Technology in Gaithersburg, Md., U.S.A. Julio
C. Gutiérrez-Vega is with the Tecnologico de
Monterrey in Mexico.
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