The science and technology of photonics—generating, detecting, amplifying and otherwise controlling light—affects various fields. Let us look at recent developments in photonics in ‘light’ of its applications in IT.

The computer might not have existed without electrons, but the humble proton too plays a rather powerful role in IT. Photonics is all about generating and controlling photons, especially in visible light, and finds application in fields ranging from information technology to healthcare. Zooming in on information technology, one finds photonics at play in bar code scanners, in the lasers that are employed in printers and storage drives, in optical fibres, in display technologies, and probably in the quantum computers that might emerge in the future.Here are some of the recent advancements in photonics that spell ‘advancement’ for information technology.

Psst… I have a secret to tell you

Photonics manifests itself in telecommunications mainly as fibre optics and related communication technologies. In December 2006, researchers Bernard B. Wu and Evgenii E. Narimanov of Princeton University, New Jersey, USA, announced the results of their research, which, once fine-tuned, could result in phenomenally secure communications over public fibre optic communication networks. The idea is to spread a ‘secret signal’ over time and convey it at a low rate over a public network with other public signals. The person with the proper ‘decoder’ will know how the signal was spread and how to put it together again.

Now, this sounds like age-old technology used in military wireless communications. The innovation is that in the proposed solution, the communication is not performed at a fixed bit rate (which would make it very easy for snoopers to identify the pattern using correlation analysis). Here, the ratio of bit rates between the secret and public signals must be an integer between 100 and 1000. The secret signal always has the lower rate and is ‘masked’ by the public waveform.

The researchers noted that the use of a public network also offers a subtle but important advantage—secure networks always attract the attention of anti-social elements. But, when a public network is used, how can the instigators guess which network the communicating parties are utilising?

Of butterflies and integrated circuits

A butterfly called Morpho Peleides may well be the wind beneath the wings of a major advancement in the low-cost production of photonic integrated circuits.

Researchers at the Georgia Institute of Technology in Atlanta and Zhejiang University in Hangzhou, China, studied the scales, the lamellae and, in turn, the sub-ribs in the lamellae, of the Morpho Peleides and found that the structural arrangement of these units could well be a two-dimensional photonic crystal.