Laser pioneers win Nobel Physics Prize

Techniques used in corrective eye surgery

STOCKHOLM, Oct 2, (AFP): Three scientists on Tuesday won the Nobel Physics Prize for inventing optical lasers that have paved the way for advanced precision instruments used in corrective eye surgery and in industry, the jury said.

Arthur Ashkin of the United States won one half of the nine million Swedish kronor (about $1.01 million or 870,000 euros) prize, while Gerard Mourou of France and Donna Strickland of Canada shared the other half.

Ashkin, 96, was honoured for his invention of “optical tweezers” that grab particles, atoms, viruses and other living cells with their laser beam fingers.

With this he was able to use the radiation pressure of light to move physical objects, “an old dream of science fiction,” the Royal Swedish Academy of Sciences said.

A major breakthrough came in 1987 when Ashkin used the tweezers to capture living bacteria without harming them, the Academy noted.

Ashkin, who made his discovery while working at AT&T Bell Laboratories from 1952 to 1991, is the oldest winner of a Nobel prize, beating out American Leonid Hurwicz who was 90 when he won the 2007 Economics Prize.

Meanwhile Mourou, 74, and Strickland -- only the third woman to win the Physics Prize -- won for helping develop a method to generate ultrashort optical pulses, “the shortest and most intense laser pulses ever created by mankind,” the jury said.

Their technique is now used in corrective eye surgery.

Mourou was affiliated with the Ecole Polytechnique of France and the University of Michigan in the US, while Strickland, his student, is a professor at the University of Waterloo in Canada.

scientist over a lecture that suggested physics was “built by men” and accused women of demanding specialist jobs without suitable qualifications.

Speaking by phone to the academy, a moved Strickland said she was thrilled to receive the Nobel prize that has been the least accessible for women. “We need to celebrate women physicists because they’re out there... I’m honoured to be one of those women.”

Before her, only Marie Curie and Maria Goeppert Mayer had won the physics prize, in 1903 and 1963 respectively.

The Royal Swedish Academy of Sciences has in the past lamented the small number of women laureates in the science fields in general.

It has insisted that it is not due to male chauvinism bias on the award committees, instead attributing it to the fact that laboratory doors were closed to women for so long.

Predicted

Last year, US astrophysicists Barry Barish, Kip Thorne and Rainer Weiss won the physics prize for the discovery of gravitational waves, predicted by Albert Einstein a century ago as part of his theory of general relativity.

On Monday, two immunologists, James Allison of the US and Tasuku Honjo of Japan, won this year’s Nobel Medicine Prize for research into how the body’s natural defences can fight cancer.

The winners of the chemistry prize will be announced on Wednesday, followed by the peace prize on Friday. The economics prize will wrap up the Nobel season on Monday, Oct 8.

Here is a brief explanation of their breakthroughs and how the discoveries can be applied:

Optical tweezers: American physicist Arthur Ashkin was given one half of the prestigious award for inventing “optical tweezers” – intense laser beams that can grab microscopic particles and move them about for

The presentation by Alessandro Strumia of Pisa University was delivered Friday at the Geneva lab during a workshop on the relationship between high study.

They use light to move physical objects, “an old dream of science fiction,” according to the Royal Swedish Academy of Sciences. The beams use light’s natural radiation pressure, allowing scientists to examine and manipulate viruses, bacteria and other living cells – even individual atoms – without damaging them.

The Nobel prize committee said the innovation, which Ashkin developed in the 1970s and 1980s, had created “new opportunities for observing and controlling the machinery of life”.

Optical pulses: The other half of Tuesday’s prize pot was split between Frenchman Gerard Mourou and Donna Strickland of Canada, for their joint development of ultra-short optical pulses.

When early lasers were being developed in the 1960s, scientists encountered the problem of how to scale up the beams without also boosting their intensity to potentially dangerous levels.

Mourou and Strickland developed a technique, known as chirped-pulse amplification (CPA), which enabled researchers to boost laser power but keeping the intensity safe by having incredibly short light bursts.

CPA first stretches laser pulses over time to reduce their intensity, before amplifying them and compressing them again.

The compressed pulses saw more light packed into a shorter time, increasing the intensity of the pulse.

It enables beams to cut or drill holes in various materials, including living matter, with extreme precision.

Today the technique is used in millions of laser eye surgeries across the world and is being applied to research in several fields, including cancer care.

energy theory and gender. The presentation – which includes various slides, charts and graphs – appears to claim that men face discrimination in the field of physics.

One pictorial series suggests that women line up to take gender studies and then later protest over a lack of jobs in stem fields, an umbrella term that covers areas like chemistry and engineering. (AFP)

New species of hummingbirds:

A team of ornithologists in Ecuador has identified a new species of hummingbird: a lovely blue-green creature that lives in a cold, barren highland area and is in danger of extinction. Team leader Francisco Sornoza saw one of the birds through binoculars a year ago and had a hunch that it was a previously unknown species.

The bird is about 11 cm (four inches) long and has a stunning, deep blue neck, a white breast with a black stripe and greenish-blue head and body feathers.

It has been given the name Oreotrochilus cyanolaemus, or blue-throated star. The discovery was announced Thursday in a journal called The Auk: Ornithological Advances.

The bird lives at an altitude of 3,000 to 3,700 meters (10,000 to 12,000 feet) in an area near the Pacific coast that straddles the provinces of Loja and El Oro. Researchers estimate there are only 300 of these birds and say its habitat is shrinking dramatically. Mining in the area also threatens it. (AFP)