Bert Hecht examines an optical nanoantenna
developed using a new fabrication method
developed at the University of Würzburg.
Courtesy of Bert Hecht.
the group fabricated nanostructures that
exhibit ultrasmooth surfaces and small
gaps over extended distances, not easily
achieved using other approaches.
“The use of single-crystalline gold
allows us to produce reproducible optical
nanoantennas with very small tolerances,”
Hecht said. “Their optical properties – the
light enhancement in the feedgap – are
roughly 10 times better than for multi-
crystalline antennas.”
Although photovoltaic systems could
stand to profit from easier and cheaper
ways to produce nanoantennas, Hecht ad-
mits that rooftop solar cells probably will
benefit from cheaper and simpler methods
before nanoantennas become sufficiently
cheap and are able to be produced in large
enough arrays.
Nevertheless, the investigators plan to
follow up the potential of antennas for optoelectronic applications.
“We will further push the limits of fab-
rication to produce ultrasmall gaps, which
should yield even higher field enhance-
ment,” Hecht said. “The reproducibility
of the structures and their high precision
are instrumental for systematic studies of
such effects. It will allow us to gain a
deeper understanding of the underlying
physics.”
Marie Freebody
marie.freebody@photonics.com
