King's College London finds rainbows on nanoscale

Big impact on solar cells, television screens

2012-11-20

(Press-News.org) New research at King's College London may lead to improved solar cells and LED-displays. Researchers from the Biophysics and Nanotechnology Group at King's, led by Professor Anatoly Zayats in the department of Physics have demonstrated in detail how to separate colours and create 'rainbows' using nanoscale structures on a metal surface. The research is published in Nature's Scientific Reports.

More than 150 years ago, the discovery at King's of how to separate and project different colours, paved the way for modern colour televisions and displays. The major challenge for scientists in this discipline nowadays is the manipulation of colour at the nanoscale. This capability will have important implications for imaging and spectroscopy, sensing of chemical and biological agents and may lead to improved solar cells, flat-screen tv's and displays.

Researchers at King's were able to trap light of different colours at different positions of a nanostructured area, using especially designed nanostructures. Depending on the geometry of the nanostructure, a trapped rainbow could be created on a gold film that has the dimension on the order of a few micrometers - about 100 times smaller than the width of a human hair.

Professor Zayats explained: 'Nanostructures of various kinds are being considered for solar cell applications to boost light absorption efficiency. Our results mean that we do not need to keep solar cells illuminated at a fixed angle without compromising the efficiency of light coupling in a wide range of wavelengths. When used in reverse for screens and displays, this will lead to wider viewing angles for all possible colours.'

The big difference to natural rainbows - where red always appears on the outer side and blue on the inner side - is that in the created nanostructures the researchers were able to control where the rainbow colours would appear by controlling the nanostructures' parameters. On top of this, they discovered that it is possible to separate colours on different sides of the nanostructures.

Co-author Dr Jean-Sebastien Bouillard from King's said: 'The effects demonstrated here will be important to provide 'colour' sensitivity in infrared imaging systems for security and product control. It will also enable the construction of microscale spectrometers for sensing applications.'

The ability to couple light to nanostructures with multicolour characteristics will be of major importance for light capturing devices in a huge range of applications, from light sources, displays, photo detectors and solar cells to sensing and light manipulation in optical circuits for tele- and data communications.

INFORMATION:

NOTES TO EDS

Paper title: 'Broadband and broadangle SPP antennas based on plasmonic crystals with linear chirp' (pdf of final paper available upon request)
Nature's Scientific Reports
http://www.nature.com/scientificreports, DOI: 10.1038/srep00829

[Attachments] See images for this press release:

ELSE PRESS RELEASES FROM THIS DATE:

'Obese but happy gene' challenges the common perception of link between depression and obesity

2012-11-20

Hamilton, ON (November 20, 2012) – Researchers at McMaster University have discovered new genetic evidence about why some people are happier than others. McMaster scientists have uncovered evidence that the gene FTO – the major genetic contributor to obesity – is associated with an eight per cent reduction in the risk of depression. In other words, it's not just an obesity gene but a "happy gene" as well. The research appears in a study published today in the journal Molecular Psychiatry. The paper was produced by senior author David Meyre, associate professor in clinical ...

JTCC researchers play important role in groundbreaking study that may change transplant practices

2012-11-20

Hackensack, NJ (November 20, 2012) – Researchers from John Theurer Cancer Center at Hackensack University Medical Center, one of the nation's 50 best cancer centers, played an important role in a study published in the New England Journal of Medicine on October 18 that may change the current blood and marrow transplantation practices. The phase 3, multicenter study compared harvesting stem cells from bone marrow rather than blood and suggests there are benefits to both approaches, but no survival differences between the two methods. Over the past 10 years, 75 percent ...

Nanotech device mimics dog's nose to detect explosives

2012-11-20

(Santa Barbara, CA —) Portable, accurate, and highly sensitive devices that sniff out vapors from explosives and other substances could become as commonplace as smoke detectors in public places, thanks to researchers at University of California, Santa Barbara. Researchers at UCSB, led by professors Carl Meinhart of mechanical engineering and Martin Moskovits of chemistry, have designed a detector that uses microfluidic nanotechnology to mimic the biological mechanism behind canine scent receptors. The device is both highly sensitive to trace amounts of certain vapor molecules, ...

Nanomedicine breakthrough could improve chemotherapy for childhood cancer

2012-11-20

In a world-first, researchers from the Australian Centre for Nanomedicine at the University of New South Wales (UNSW) in Sydney have developed a nanoparticle that could improve the effectiveness of chemotherapy for neuroblastoma by a factor of five. Neuroblastoma is an aggressive childhood cancer that often leaves survivors with lingering health problems due to the high doses of chemotherapy drugs required for treatment. Anything that can potentially reduce these doses is considered an important development. The UNSW researchers developed a non-toxic nanoparticle ...

Rituximab shows promise for clinical problems tied to antiphospholipid antibodies

2012-11-20

Rituximab, a drug used to treat cancer and arthritis, may help patients with antiphospholipid antibodies (aPLs) who suffer from aPL-related clinical problems that do not respond to anticoagulation, such as cardiac disease and kidney disease, according to a new study by rheumatology researchers at Hospital for Special Surgery. The study appears online ahead of print, in the journal Arthritis and Rheumatism. "This is the first study to systematically analyze rituximab in aPL-positive patients. Rituximab may have a role in treating a subgroup of aPL patients," said Doruk ...

VTT: A low-carbon Finland is a great challenge, but an achievable one

2012-11-20

VTT specialists have assessed Finland's chances of achieving the 80% greenhouse gas emission reduction targets. The EU's goal for 2050 is to reduce emissions by at least 80% from the level of 1990. The goal is a tough one for Finland, but possible to achieve as long as all sectors that produce or consume energy take part. On top of this, all greenhouse gas emissions must be reduced. Finland requires new technological solutions for industrial activity, for the transport of people, goods and services, and for housing and working methods. If clean forms of energy and the ...

Europe must not lose momentum in marine biodiversity research

2012-11-20

A new Marine Board Future Science Brief presents a roadmap for marine biodiversity science in Europe and warns against complacency. The ocean provides 95% of the habitable space on Earth and harbours a vast diversity of life. Biodiversity underpins the health of the oceans and their productive ecosystems which are essential for human well-being and prosperity. But marine life is under significant threat from climate change and from increasing human impacts including pollution, overfishing and ocean acidification. Marine biodiversity research and its role in supporting ...

Gastric bypass surgery: Follow up as directed to lose more

2012-11-20

Gastric bypass patients who attended five follow-up office visits in two years as recommended by their surgeons lost nearly twice as much weight (113 lbs. vs. 57 lbs.) as patients who attended only two follow-up visits, according to a University of Pennsylvania School of Nursing study in Obesity Surgery. The global epidemic of overweight and obese people is estimated to include 1.7 billion individuals, with two-thirds of those living in the U.S. Measurement of body mass index (BMI), a calculation of height and weight, classifies obesity. Patients with severe obesity ...

Sweat glands play major role in healing human wounds, U-M research shows

2012-11-20

ANN ARBOR, Mich. — Turns out the same glands that make you sweat are responsible for another job vital to your health: they help heal wounds. Human skin is rich with millions of eccrine sweat glands that help your body cool down after a trip to the gym or on a warm day. These same glands, new University of Michigan Health System research shows, also happen to play a key role in providing cells for recovering skin wounds – such as scrapes, burns and ulcers. The findings were released online ahead of print in the American Journal of Pathology. "Skin ulcers – including ...

King's Water Research Group co-convenes global conference on food and water security

2012-11-20

A team of experts from King's College London have played a major role in delivering an international conference on food and water security in Qatar this week. The Food Security in Dry Lands (FSDL) conference has been organised in the run up to the forthcoming UN climate meeting (COP18) later this month, where 'climate-smart' agriculture is expected to be a key focus. The King's Water Research Group have contributed to the new Doha Declaration, which states that by 2022, participating countries -Qatar, Kenya, Tanzania, Chad, Egypt, Jordan, Saudi Arabia, South Africa, Nigeria, ...

A new paradigm in spectroscopic sensing: The revolutionary leap of SERS-optical waveguide integration and ai-enabled ultra-sensitive detection

Pusan National University study highlights the health hazards of ultrafine particles from small home appliances with electric heating coils and brushed DC motors

King's College London finds rainbows on nanoscale

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: