Telecoms ♦ news digest on refracted light.
To overcome these problems, researchers working at NIST took inspiration from a theoretical metamaterial design recently proposed by a group at the FOM Institute for Atomic and Molecular Physics in Holland. They adapted the design to work in the UV- a frequency range of particular technological interest.
According to co-authors Xu, Amit Agrawal and Henri Lezec, aside from achieving record-short wavelengths, their metamaterial lens is inherently easy to fabricate. It doesn’t rely on nanoscale patterns, but instead is a simple sandwich of alternating nanometre-thick layers of silver and titanium dioxide, the construction of which is routine.
And because its unique design consists of a stack of strongly coupled waveguides sustaining backward waves, the metamaterial exhibits a negative index of refraction to incoming light regardless of its angle of travel.
The researchers say this realisation of a Veselago flat lens operating in the UV is the first such demonstration of a flat lens at any frequency beyond the microwave. By using other combinations of materials, it may be possible to make similarly layered metamaterials for use in other parts of the spectrum, including the visible and the infrared.
The metamaterial flat lens achieves its refractive action over a distance of about two wavelengths of UV light, about half a millionth of a metre - a focal length challenging to achieve with conventional refractive optics such as glass lenses.
What’s more, transmission through the metamaterial can be turned on and off using higher frequency light as a switch, allowing the flat lens to also act as a shutter with no moving parts.
“Our lens will offer other researchers greater flexibility for manipulating UV light at small length scales,” says Lezec. “With its high photon energies, UV light has a myriad of applications, including photochemistry, fluorescence microscopy and semiconductor manufacturing. That, and the fact that our lens is so easy to make, should encourage other researchers to explore its possibilities.”
The new work was performed in collaboration with researchers from the Maryland NanoCentre at the University of Maryland, College Park; Syracuse University; and the University of British Columbia, Kelowna, Canada.
More details of this work has been published in the
paper, “All-angle negative refraction and active flat lensing of ultraviolet light,” by T. Xu et al in Nature, 497, 470–474, published online on May 23rd, 2013. DOI:10.1038/nature12158
Telecoms
Infinera InP DTN-X platform to be deployed in New Zealand
The firm’s indium phosphide PICs will be used in delivering 10, 40 and 100 Gigabit Ethernet (GbE) services
FX Networks, an owner and operator of a national network in New Zealand, has selected the Infinera DTN-X platform for its nationwide network.
The Infinera DTN-X, featuring 500 Gigabit per second (Gb/s) long haul super-channels enables FX Networks to build a new network infrastructure delivering 10, 40 and 100 Gigabit Ethernet (GbE) services to service providers and research and education networks.
FX Networks, a new DTN-X customer for Infinera, owns and operates a national high-capacity inter-city fibre optic network throughout New Zealand. FX Networks partnered with REANNZ, New Zealand’s Research and Education Network, to build this multi-terabit countrywide network.
The innovative arrangement included joint investment and fibre sharing between the two entities to increase the capacity and footprint of the network. This new infrastructure will provide a multi-terabit network to offer scientists across New Zealand the opportunity to participate in the world’s most cutting edge and data intensive experiments.
FX Networks, who will operate the network under the agreement with REANNZ, selected the Infinera DTN-X platform to deliver 500 Gb/s coherent super-channels on its network, along with its future scalability to one Terabit per second (Tb/s) super-channels. The super channels feature an integrated OTN switch and are operated using simple open intelligent software.
FX Networks also plans to offer 10, 40 and 100 GbE services to a broad set of wholesale customers across New Zealand and will leverage the ability of the DTN-X to deliver these services quickly.
July 2013
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