Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers have knots in light all tied up

12.11.2004


Researchers from the Universities of Southampton and Glasgow have succeeded in tying knots in light beams.



Using a computer-designed hologram, they created threads of darkness embedded in a laser beam. The hologram bends the direction of optical energy flow, so these dark threads form loops. The loops can then be linked together, or tied into knots.

Dr Mark Dennis, a University of Southampton mathematician, worked in collaboration with Professor Miles Padgett, Dr Johannes Courtial, and Jonathan Leach in the Optics group in the University of Glasgow’s Department of Physics and Astronomy. Their findings are set out in a paper ‘Knotted threads of darkness’ which is published in Nature this week (11 November 2004).


Dr Dennis made the detailed calculations required to find the ideal mathematical form for the knotted laser beams while he was a Leverhulme Fellow based at the University of Bristol. He recently took up the post of Royal Society Research Fellow in the School of Mathematics at Southampton.

The role of the Glasgow group was designing the hologram that produced the exact combination of beams required to form the loops and knots. A laser was used to illuminate the hologram and the detailed structures recorded by a sensitive camera.

This work is experimental confirmation of earlier theoretical predictions made by Dr Dennis, with Professor Sir Michael Berry at the University of Bristol. Scientifically the work dates back to Lord Kelvin, who tried to formulate a theory for atoms made of loops and knots, embedded not within light, but in the fictitious ether.

Dr Dennis explains: ‘In the present day, the ability to synthesize such knots demonstrates the precise three-dimensional control it is possible to exert over light. These dark loops, links and knots are exciting structures in themselves. They could also be used as traps for quantum mechanical matter such as Bose-Einstein condensates which are matter waves on a macroscopic scale.’

Sarah Watts | alfa
Further information:
http://www.soton.ac.uk

More articles from Physics and Astronomy:

nachricht A better way to weigh millions of solitary stars
15.12.2017 | Vanderbilt University

nachricht A chip for environmental and health monitoring
15.12.2017 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>