The 2018 Nobel Prize in physics was awarded to scientists who advanced the development of lasers into fields as different as eye surgery and manipulating objects as tiny as viruses and other living cells, the Royal Swedish Academy of Sciences announced on Tuesday in Stockholm.
American Arthur Ashkin of the old Bell Laboratories was awarded one half of the 9 million Swedish kronor ($1.01 million) prize for “optical tweezers,” and the other half went to France’s Gérard Mourou and Donna Strickland of Canada’s University of Waterloo for laser advances that were turned into the beams that correct nearsightedness.
Strickland, 59, was the first woman to win a physics Nobel since 1963 and only the third in history. “I’m honored to be one of those women,” she told the Nobel gathering.
Asked what her first reaction to the news was, Strickland told the press conference announcing the prize, “First of all, you have to think it’s crazy, so that was my first thought.”
Ashkin, 96, began his work soon after the invention of the laser in 1960, and by the 1980s had realized a science fiction dream: moving objects with only the pressure of a light beam. Optical tweezers grab viruses and other living cells “with their laser beam fingers,” the Nobel committee explained. By 1987 he had used the tweezers to capture bacteria, a technique now commonly used to study living systems, including to study the “biological motors” that move molecules within a cell as well as cells themselves.
The biological uses of optical tweezers came abuot serendipitously. Trying to capture smaller and smaller particles, Ashkin tried his lasers on samples of viruses. One morning, after he had left them overnight, the samples contained large particles that moved “hither and thither,” as the Nobel committee charmingly put it. The particles turned out to be bacteria that, when they approached the laser beam, were caught in the light trap.
Optical tweezers have also become a workhorse of synthetic biology, where they fuse together synthetic membranes, for instance, in experiments trying to create living cells.
Ashkin is the oldest-ever Nobel laureate. When Göran Hansson, who announced the prize and is the secretary general of the Royal Swedish Academy of Sciences, reached him by phone and asked if he could speak to reporters, Ashkin said he was too busy with his latest paper.
Mourou, 74, and Strickland, then at the University of Rochester, invented chirped pulse amplification, a form of high-intensity laser, as they described in a 1985 paper that was Strickland’s first scientific publication. Their joint Nobel represents an extremely rare instance in which a graduate student (as Strickland then was) who does the lion’s share of the bench science is honored along with the senior scientist.
Strickland had became attracted to laser physics for not only scientific but also aesthetic reasons: She noticed the green and red beams that shone throughout Mourou’s lab like a Christmas tree. The team created ultrashort, high-intensity laser pulses, essentially packing more light than standard lasers in the same tiny space. That increases the pulse intensity, which has found its most practical use in corrective eye surgeries.