Ultrafast Photography

University of Ottawa physicist captures prestigious Canadian research prize

Ottawa, Ontario, March 11, 2004 – Faster than a speeding bullet? Big deal, says theoretical physicist Dr. Thomas Brabec. That kind of speed doesn't even register on his notion of fast. Brabec is in the vanguard of a brand of physics that promises the unimaginable: an atomic-level camera that uses ultrafast pulses of light to produce freeze-action images of nuclear and electron processes.

“It's an idea or concept at the moment. If it works, it's revolutionary. But there are many obstacles to be overcome,” says Dr. Brabec, the Canada Research Chair in Ultrafast Photonics at the University of Ottawa.

If anyone can help turn the idea into reality, it's Dr. Brabec. In the mid-1990s, during and shortly after his Ph.D. work at the Vienna University of Technology in Austria, Dr. Brabec developed the theoretical underpinnings for the creation of femtosecond (10^-15 seconds) solid-state laser pulses. This led to the generation of five femtosecond laser pulses (five-millionths of a billionth of a second), the world's fastest at the time.

Brabec’s internationally acclaimed work today captured him an NSERC Steacie Fellowships, one of Canada’s science and engineering honours.

The award was among six announced today by Lucienne Robillard, Minister of Industry and Minister responsible for the Economic Development Agency of Canada for the Regions of Quebec, and Dr. Tom Brzustowski, President of NSERC.

“NSERC Steacie Fellows are quickly rising to the top of their fields while providing role models for younger scientists and engineers,” said Minister Robillard. “Through their creativity and excellent research, they are helping Canada build the knowledge base needed for a 21^st century economy.”

“These awards are public recognition for outstanding scientific achievement,” said Dr. Brzustowski. “The researchers honoured today have already started their careers in an incredible way and I know that they will do great things for science in Canada.”

As ultrafast camera flashes, these femtosecond pulses have become the new standard for watching and better understanding chemical reactions. But in describing his latest work, Dr. Brabec lets slip that he thinks these femtosecond laser flashes are now electromagnetic slow-pokes. He has his theoretical sights set a thousand times faster, on attosecond (10^-18 seconds) pulses. An athlete who won a race by an attosecond would be ahead by less than the width of an atom.

Though still in its embryonic stage, attosecond science holds the promise of resolving a new atomic and molecular horizon by using speeds and wavelengths of energy that can see nuclear and electron-level details.

The technique works by using a high-energy, ultrafast laser to rip electrons from their nuclei, creating ionized (or negatively and positively charged) particles. The laser field has positive and negative cycles, so when the cycle reverses, the now accelerated charged particles crash together, releasing a flash of intense x-ray energy. It's this burst of faster, shorter wavelength x-rays that can be used to image the attosecond-speed movements of electrons or nuclear processes.

“It's like a stroboscope,” says Dr. Brabec. “You have these flashes and one flash freezes the electron at one position, and then comes the next flash and it freezes the electron at a slightly different position. It's like the famous 19^th century images of the galloping horse caught in stop-action photography.”

Brabec says the research time, and money for graduate students, that the NSERC Steacie Fellowship provides will enable him to accelerate his own work to making attosecond science an applied reality.

For this master of speed, though, the most tantalizing goal is the visualization of electron behaviour using attosecond pulses. To achieve this, his group is finessing a unique computer code that could open the door to the attosecond analysis of electron behaviour in complex atoms and molecules, something that's been dubbed the Holy Grail of chemistry.

NSERC, now also known as Science and Engineering Research Canada, is a key federal agency investing in people, discovery, and innovation. It supports both basic university research through research grants, and project research through partnerships among postsecondary institutions, government and the private sector, as well as the advanced training of highly qualified people.

Contacts:

Dr. Thomas Brabec
Tel.: (613) 562-5800, ext. 6756
E-mail: brabec@uottawa.ca

Arnet Sheppard
NSERC
Tel.: (613) 995-5997
E-mail: arnet.sheppard@nserc.ca

The Prize

NSERC Steacie Fellowships are awarded to outstanding Canadian university scientists or engineers, who have earned their doctorate within the last 12 years, and whose research has already earned them an international reputation. Nominations are received by NSERC from universities across Canada and judged by a distinguished panel of independent experts. The awards include increased research funding from NSERC and payments to the universities to allow the Steacie Fellows to pursue their research full-time. They are also eligible to compete for a special Canada Foundation for Innovation Career Award. The announcement of these awards will be made later.

The six winners this year are:

• Dr. Mosto Bousmina – Université Laval
• Dr. Thomas Brabec – University of Ottawa
• Dr. George Eleftheriades – University of Toronto
• Dr. Lisa Jeffrey – University of Toronto
• Dr. Eric Hessels – York University
• Dr. Patrick Keeling – University of British Columbia

Dr. Edgar William Richard Steacie, for whom the awards are named, was a physical chemist and President of the National Research Council from 1952 to 1962. He strongly believed that:

• fundamental research is essential to the development of science;
• the individual is key to research, and individual ideas are ultimately responsible for important advances in science;
• there are no national boundaries in science; and
• complete freedom is required for creative work.

Dr. Steacie felt that promising young scientists are our greatest asset and should be given every opportunity to develop their own ideas. Through the NSERC Steacie Fellowships, his philosophy lives on.