One half of the Prize went to Arthur Ashkin for his discoveries of optical tweezers and their application to biological systems. During the 1970s and 1980s he was able to capture particles, atoms, viruses and other living cells with laser beam fingers from his invention, optical tweezers. By using the radiation pressure of light he was able to move physical objects and was able to push small particles towards the center of the beam and hold them there. The effect was demonstrated by the award committee by levitating a ping pong ball with a hairdryer. In 1987 Ashkin captured living bacteria for the first time, without harming them. 

In 1987 Ashkin captured living bacteria for the first time, without harming them. 

In an interview with Nobel Media right after the announcement Ashkin said, “My famous paper in 1970 – that’s the most famous paper I ever wrote. In that I mention capturing molecules with light, but I never thought living things – light was supposed to kill tissue. They used light to heal wounds and it was considered to be deadly. That was very much a surprise. That was a big surprise and once I look, well I should, I’ve got a lot of old stories to tell about what happened. When I described catching living things with light people said, ‘Don’t exaggerate Ashkin!”

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Arthur Ashkin: The power of light

Dr. Arthur Ashkin, PhD, knew 40 years ago he had developed something special. Now the rest of the world knows it. 

His invention is now used all over the world to study the machinery of life. The optical tweezers provided the foundation for the 1997 Nobel Prize in Physics, which was awarded for trapping atoms.

Chirped pulse amplification

The other half of the Nobel Prize in Physics went to Gérard Mourou and Donna Strickland. They demonstrated how to create ultrashort, intense bursts of laser light by stretching, amplifying and finally recompressing light waves. In 1985 they published the article that would lead to the Prize, it was also the foundation of Strickland’s doctoral thesis.

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Gérard Mourou: The eureka moment

A passion for laser physics has been the guiding light for Gérard Mourou throughout his entire career. Even in 1957, he could see the limitless potential of this nascent field of science. What he didn’t envision then is that one day his discoveries would lead to winning the 2018 Nobel Prize in Physics. 

They had succeeded in creating ultrashort high-intensity laser pulses without destroying the amplifying material. Their newly invented technique, called chirped pulse amplification, CPA, soon became standard for subsequent high-intensity lasers. Its uses include the millions of corrective eye surgeries that are conducted every year using the sharpest of laser beams. The technique is also used in cancer treatment. Doctors use these pulses in laser eye surgery to cut open the top layer of the cornea and remove tissue underneath. This reshaping of the cornea moves the eye’s focal point and can correct near-sightedness.

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Donna Strickland: “It’s all about the science”

Science has always been a driving force in Donna Strickland’s life. From the moment she discovered the world of laser physics, she’s been entranced by all the possibilities lasers represent for research, science and medicine.

In a phone interview with the Swedish Academy, Strickland said her favorite application of high-power lasers is white light generation. With this technique, a beam containing a narrow range of wavelengths is shot into a medium, such as water, causing the waves to spread out into a rainbow. This is more advanced than Newton’s famous experiment with a prism; whereas he simply spread out light into its component colors, white light generation broadens the spectrum contained within a beam, creating the colored light.

“It’s a remarkable thing to see,” Strickland says, and it took decades for physicists to understand how it worked. “But that’s what scientists like to do, puzzle over something.”