Nobel Laureate and Honorary Member Arthur Ashkin was known for his pioneering work to create optical tweezers. He received a B.A. in physics from Columbia College, U.S. in 1947 and a Ph.D. in nuclear physics from Cornell University, U.S., in 1952. Ashkin worked at the Columbia Radiation Lab from 1942 to 1945 while in the Army and at AT&T Bell Laboratories from 1952 to 1991. At Bell Labs, Ashkin researched microwaves, nonlinear optics and laser trapping. With colleagues, he made the first observation of continuous-wave (cw) laser harmonic generation, cw parametric amplification, discovered the photorefractive effect, and initiated the field of nonlinear optics in optical fibers.
Many consider Ashkin the father of laser radiation pressure. His work in this area concerned the optical trapping and manipulation of small dielectric particles using optical gradient forces. Ashkin achieved many “firsts.” He was the first to observe optical gradient forces on atoms and the first to perform laser cooling of atoms known as “optical molasses.” He also was the first to observe the optical trapping of atoms.
Ashkin extended this work to the trapping and manipulation of living materials such as bacteria, viruses, and cells. The laser technique for holding material in place became known as “optical tweezers.” Using this approach, Ashkin explored the interior of a cell, manipulating its inner structures, and laying the foundation for new ways to understand normal and diseased states in the human body. The ability to cool and trap atoms has led to spectacular advances in basic science, such as the creation of Bose-Einstein condensates in atomic vapor.
Ashkin was the author of Optical Trapping and Manipulation of Neutral Particles Using Lasers and holds 47 patents. Awards and honors recognizing his scientific contributions include election to the National Academy of Engineering and the National Academy of Sciences, OSA’s Ives Medal/ Quinn Award and Townes Award, the IEEE Laser and Electro-Optic Society’s Quantum Electronics Award, the APS Joseph F. Keithley Award for advances in measurement science, and the Rank Prize in opto-electronics. Ashkin was elected fellow of APS, OSA, IEEE, and AAAS.
In 2009, he was named an Honorary Member of the Optical Society for his pioneering work on optical trapping and the development of optical tweezers.
On 2 October 2018, Ashkin was awarded the Nobel Prize in Physics for his work on optical trapping. Ashkin was awarded half of the prize while the other half was shared between Gérard Mourou and Donna Strickland.
Ashkin died in 2020 at the age of 98.
Arthur Ashkin died on 21 September 2020, please see OSA's memorial entry.
Well, this is my life's work. It has to do with radiation pressure, the pressure of light. I'm going to give you a little lecture. When light shines on you, it pushes on you. Everybody knows that light has heat. The sun is hot. But the fact is, the sun pushes on you. And with lasers, if you focus the light down to very small spots, you can actually push things or pull, it turns out. Push, pull, make what they call optical traps. So I am the inventor of the optical trap, and it sort of started in that very strange way. Just by accident.