Scientists create world's most efficient light-bulbAugust 27, 2003Scientists have successfully produced the most efficient light bulb ever - but on the microscopic scale. Researchers at Trinity College, Dublin have discovered a technique which significantly improves the output of light from quantum dots, and also allows their light to be focussed and manipulated easily. Their findings are published today in the Institute of Physics journal Semiconductor Science and Technology. Dr Yuri Rakovich and Dr John Donegan from Trinity College, Dublin working with researchers at the universities of Hamburg and Munich, have successfully placed quantum dots (the most efficient light-bulb in the world) onto a tiny polymer sphere. Scientists have known for some time that quantum dots (tiny particles made from certain semiconducting materials) have numerous applications as they are capable of producing light without wasting any energy as heat. They are the basic unit of quantum computers - computers around 10,000 times faster that the fastest computer currently in use. John Donegan's team have found that they can make quantum dots more efficient than ever. By embedding quantum dots on the surface of a microsphere they can enhance the output of light from these quantum dots by a factor of 20 and - because these structures are spherical - they allow the light emitted from the quantum dots to be focussed into a fine beam which can be moved around easily by the researcher. The Trinity College team's work has been carried out entirely under the microscope. They took a polymer microsphere of about 5 microns in diameter (one twentieth the diameter of a human hair) and coated the surface with quantum dots made of cadmium telluride, a semiconductor similar to gallium nitride. Once the surface of the microsphere was fully coated in quantum dots, they observed the surface emitting light in different colours; in this case red and green. Dr Donegan and his team have been trying to improve the efficiency of light emission from quantum dots so that they can create a beam of light as tightly focussed as possible. These beams have a large number of possible applications and are likely to be applied to all branches of quantum technology in the future (computing, mobile phones, energy production). Dr Donegan's team are particularly interested in the manipulation of single strands of DNA. They are able to produce beams of light thin enough to be capable of manipulating a single strand of DNA, stretching it and reading the genetic information. Devices which can do this with light have been dubbed "optical tweezers" but Donegan's group believe they can now create a beam of light much finer than ever before and one which can be manipulated much more easily than previously thought possible. Dr Donegan said: "We hope that our microcavity will help in all possible applications of quantum dots but especially in our ability to manipulate physically single strands of DNA. It could have major uses in genetic analysis and in gene sequencing where the ability to handle DNA strands with increasing accuracy and dexterity is becoming ever more important". | |||||||||||||||||||||
|
Related DNA Current Events and DNA News Articles Bold traveler's journey toward the center of the Earth The first ecosystem ever found having only a single biological species has been discovered 2.8 kilometers (1.74 miles) beneath the surface of the earth in the Mponeng gold mine near Johannesburg, South Africa. Brainy genes, not brawn, key to success on mussel beach It's hard being a mussel: you have to worry about hungry starfish and even hungrier humans, not to mention an environment that can change your body temperature 50 degrees Fahrenheit in just a few hours. Opening a can of worms: Serendipitous discovery reveals earthworms more diverse than first thought Scientists have found that the UK's common or garden earthworms are far more diverse than previously thought, a discovery with important consequences for agriculture. RNA molecules, delivery system improve vaccine responses, effectiveness A novel delivery system that could lead to more efficient and more disease-specific vaccines against infectious diseases has been developed by biomedical engineers at The University of Texas at Austin. New tool probes function of rice genes A new tool for investigating the rice genome has been developed by researchers at UC Davis led by Pamela Ronald, professor of plant pathology. Researchers discover how infectious bacteria can switch species Scientists from the Universities of Bath and Exeter have developed a rapid new way of checking for toxic genes in disease-causing bacteria which infect insects and humans. DNA could reveal your surname Scientists at the world-leading Department of Genetics at the University of Leicester - where the revolutionary technique of genetic fingerprinting was invented by Professor Sir Alec Jeffreys- are developing techniques which may one day allow police to work out someone's surname from the DNA alone. Field Museum provides gold standard for mammal survey Putting together the Who's Who of bats, bears, beaked whales and all of Earth's other known mammals was a gigantic task ably assisted by a Field Museum scientific team with access to one of the planet's most extensive and diverse mammal collections. U of T researchers reveal Epstein-Barr virus protein contributes to cancer Researchers at the University of Toronto have discovered that the EBNA1 protein of Epstein-Barr virus (EBV) disrupts structures in the nucleus of nasopharyngeal carcinoma (NPC) cells, thereby interfering with cellular processes that normally prevent cancer development. Study finds genetic variant plays role in cleft lip University of Iowa researchers and collaborators have found, in a previously identified gene, a variation that likely contributes to one in five cases of isolated cleft lip. More DNA Current Events and DNA News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||