Negative-index material modulates light Oct 31, 2007 1 comment
One drawback of so-called negative-index metamaterials (NIMs) is
that they tend to absorb much of the infrared light passing
through them. Now a team of US researchers has turned that
shortcoming to their advantage, using it to design a new type of
optical modulator that promises to be faster and more compact
than existing devices (App. Phys. Lett. 91 173175). The
researchers, from Hewlett-Packard Laboratories in Palo Alto, and
University of California, Berkeley, claim this is the first time
that optical modulation has been seen in a NIM at near infrared
wavelengths. An optical modulator is a device that encodes
information in a beam of light by changing the intensity of the
light to create trains of pulses. The team based their modulator
on a "fishnet" NIM, because this structure is known to have both
a negative electrical permittivity and a negative magnetic
permeability for infrared light a certain wavelengths. As well
as being responsible for