Dr Lu (left) with
student Jiong Yang, with the lens on screen. Image Stuard Hay, ANU
(March 11, 2016) Scientists
have created the world's thinnest lens, one two-thousandth the thickness of a
human hair, opening the door to flexible computer displays and a revolution in
miniature cameras.
Lead researcher Dr Yuerui (Larry) Lu from ANU Research
School of Engineering said the discovery hinged on the remarkable potential of
the molybdenum disulphide crystal.
"This type of material is the perfect candidate for
future flexible displays," said Dr Lu, leader of Nano-Electro-Mechanical
System (NEMS) Laboratory in the ANU Research School of Engineering.
"We will also be able to use arrays of micro lenses to
mimic the compound eyes of insects."
The 6.3-nanometre lens outshines previous ultra-thin flat
lenses, made from 50-nanometre thick gold nano-bar arrays, known as a
metamaterial.
"Molybdenum disulphide is an amazing crystal,"
said Dr Lu
"It survives at high temperatures, is a lubricant, a
good semiconductor and can emit photons too.
"The capability of manipulating the flow of light in
atomic scale opens an exciting avenue towards unprecedented miniaturisation of
optical components and the integration of advanced optical
functionalities."
image: Stuard Hay,
ANU
Molybdenum disulphide is in a class of materials known as
chalcogenide glasses that have flexible electronic characteristics that have
made them popular for high-technology components.
Dr Lu's team created their lens from a crystal
6.3-nanometres thick - 9 atomic layers - which they had peeled off a larger
piece of molybdenum disulphide with sticky tape.
They then created a 10-micron radius lens, using a focussed
ion beam to shave off the layers atom by atom, until they had the dome shape of
the lens.