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Hanover
But its origins lie, at least in part, in a basement of the Dartmouth College campus.
Researchers from three countries – Donna Strickland of Canada, Gerard Mourou of the United States of America and Arthur Ashkin of the United States – have awarded one of the highest scientific honors research on real optical tweezers and high intensity laser pulses that can be used to move material. world.
This honor was long overdue, according to a Dartmouth professor who knows the subject and its story very well.
"This award has taken me a bit by surprise," said Kevin Wright, an assistant professor of physics and astronomy at Dartmouth, whose research focuses on the same field.
"I have known these people for some time. I'm not sure, but talking about myself, I thought that art had been neglected for a long time, "he said, referring to Ashkin.
Outside the laser research community, few people know that the idea of "light pressure" at the base of the entire field originates from the same lab on the Dartmouth campus where they work. Wright.
"It's good to work in a place with such a history," he said.
History of light
In 1900, Dartmouth researchers Ernest Fox Nichols and Gordon Ferrie Hull met in the Wilder laboratory with an impossible mission: to demonstrate in a laboratory that light could exert pressure on material objects.
They were working in the new three-story Wilder Lab, which is now part of the Sherman Fairchild Physical Sciences Center.
Although the Wilder Lab was considered to be at the cutting edge of technology when it was built in 1899, it was rudimentary by today's standards – steam heated, with "lantern spotlights" for physics courses at first floor and a telephone switchboard allowing researchers to speak from 11 separate lab rooms.
Like many scientific activities of the time, the biggest obstacles Nichols and Hull faced were their own instruments. Measuring the minute amount of force that could be exerted by a beam of light was considered almost impossible.
"All previous attempts to experimentally observe this effect had been thwarted … even in the best vacuum cleaners we could do at the time," according to a Nichols-Hull story written for the "Pressure of Light" Symposium in Dartmouth. several years ago. since.
Nichols and Hull have purchased the best possible equipment, including an exceptionally accurate electronic circuitry called a Wheatstone bridge, regulating motors and galvanometers that can measure slight fluctuations in electrical charges and the position of objects. Each bit of data has been carefully recorded by hand in newspapers (which are still kept at the Rauner Library).
But the most important element of their arsenal was to be built from scratch: the Nichols Radiometer. Just outside the carefully constructed bell, scientists could use magnets to alter the position of two small mirrors, hanging from the quartz threads in the void. The mirrors acted as a sort of ladder. By comparing their reaction when beams of light were directed to the glossy and blackened sides of the mirrors, they documented measurements describing for the first time the light's ability to displace the material. .
Today, their work is considered one of the most important physics experiments of all time, and the Nichols radiometer is presented at the Smithsonian Institution in Washington. The Historic Sites Committee of the American Physical Society has designated the building as a historic site.
Light of the future
The Nichols-Hull experiment served as a foundation for generations of physicists.
In recent decades, the ability to understand and manipulate light pressure has led to practical applications ranging from eye surgery to laser enhancement of atomic clocks to the removal of detonators of ancient nuclear warheads. It is promising for applications even more difficult to believe, such as changing the composition of clouds to affect precipitation.
In 1986, Ashkin used technology to invent optical tweezers that could identify a small sphere of glass or a virus.
Wright is a person who continues to push the boundaries of what light can do. Before coming to Dartmouth, Wright worked in the same premises as Strickland and Mourou at the University of Rochester. Today, Wright is working in the basement of the Wilder Lab, directly under the space where the Nichols Radiometer has been operating.
"The idea of holding a bacterium in a focused laser is still a kind of strange idea," Wright said.
And yet, Wright goes further.
Using light as a tool to fix atoms and relying on precise measurements of an optical atomic clock, Wright was able to delve deeper into the nature of quantum physics.
"My job is to shape these laser beams so that the atoms are arranged in different ways in the space," he said. The different configurations of atoms exhibit different physical properties, which means that Wright is essentially able to create designer materials that would seem almost magical to the average man.
Most of Wright's research takes place in the laboratory, in "ultra-cold" rooms, where the temperature has been cooled to nearly 460 degrees Celsius – as close as possible to the human point of view.
Strange things happen to small particles at these temperatures.
For example, use a spoon to create a small hot tub in a glass of water. Under normal conditions, this water stops swirling, overcome by the friction force. But in extremely cold environments, a phenomenon called superfluidity allows the vortex to occur, in theory, forever.
Some particles also demonstrate another scientific grail: superconductivity or the ability to conduct electricity without any loss of energy. Wright called these properties the "deep laws" of nature, playing out on a microscopic scale.
According to Wright, one of the challenges facing physicists is to maintain these properties in larger particle groups.
"In some special materials, these deep laws apply to large scales and give properties very surprising and surprising properties," he said.
Trend of the kind
College officials pointed out that Dartmouth also had links with Frances Arnold, the bioengineer at this year's Nobel laureate, California Institute of Technology, whose work on protein enzymes earned him half a share in the Nobel Prize for announced chemistry Wednesday.
Much of the initial media coverage has focused on the fact that Arnold and Strickland are women competing successfully in a field that historically has a dramatic gender imbalance.
Strickland is only the third woman to receive a share of the Nobel Prize in Physics (the first was Marie Curie in 1903), while Arnold is the fifth woman to receive part of the Nobel Prize in Chemistry.
Every October, the Royal Swedish Academy of Sciences awards the most prestigious science awards – $ 1 million Nobel Prizes – in six different categories: Peace, Economics, Literature, medicine, physics and chemistry.
Between 1901 and 2017, 847 men – and only 49 women – had received awards.
Wright said many of his colleagues and he are hoping that this year's awards will announce a new, more equitable trend.
"There have been other awards where, I think, a junior researcher, particularly a researcher, has not been recognized," he said. "A price does not make up for all the mistakes of the past, but it is proof that there is progress."
Last year, Arnold received an honorary doctorate in science from Dartmouth and the Robert Fletcher award from the Thayer School of Engineering.
Joseph Helbe, Dean of the Thayer School of Engineering, welcomed Arnold in a public statement, stating that his award "accurately recalls that a commitment to science and an understanding of interdisciplinary relationships can improve the life of all".
Arnold, herself, speaking to the students at the 2017 Thayer School 2017 inaugural inaugural ceremony, described a landscape that combines the bells of the past with the superconductors of the future.
"We engineers build using what we have and know at the time," Arnold said in his speech. "The ignorance of the underlying physics or chemistry can be circumvented with creativity and experimentation."
She also hinted at what drives science – and scientists – to continue to explore the secrets of the universe.
"I have worked with and inspired by the greatest engineer of all time," she said. "Nature."
Matt Hongoltz-Hetling can be reached at [email protected] or 603-727-3211.
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