Ashkin, Arthur, 1922–2020, American physicist, b. Brooklyn, N.Y., Ph.D. Cornell, 1952. Ashkin worked for four decades at Bell Laboratories, retiring in 1992. Ashkin researched microwaves, nonlinear optics, laser radiation pressure, and laser trapping. He is a pioneer of the study of laser radiation pressure, the force that laser light (and other forms of radiation) can exert on objects. He demonstrated that lasers could trap and manipulate small beads. Ashkin, working with Steven Chu and others, cooled and trapped atoms using a technique known as optical molasses, then in 1986 trapped cooled atoms using a laser been focused through a lens, a technique known as optical tweezers. Ashkin then went on to use the optical tweezer technique with an infrared laser to trap living cells and manipulate their interior structures without damaging them. Optical tweezers are used in a variety of applications including studying the physical properties of DNA. For his work developing optical tweezers, Ashkin received half of the 2018 Nobel Prize in Physics; the other half of the prize was awarded to Gérard Mourou and Donna Strickland. Ashkin is also credited with discovering (1966) the photorefractive effect, a reversible, nonlinear change in the index of refraction of some materials in response to light.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2024, Columbia University Press. All rights reserved.
See more Encyclopedia articles on: Physics: Biographies
