Arthur Ashkin demonstrated that radiation pressure from a continuous laser could accelerate and trap microscopic particles. This made transfer of optical momentum a tool for controlling matter rather than merely a correction to optical measurements. Later, he and collaborators demonstrated a single-beam gradient-force optical trap: a strongly focused beam held dielectric particles in water. The optical tweezers arrangement balances the restoring effect of the intensity gradient against the forces tending to push the particle away.[ref]
Acceleration and Trapping of Particles by Radiation Pressure by Arthur Ashkin. 1970 abstract: acceleration and stable optical potential wells
[ref]Observation of a single-beam gradient force optical trap for dielectric particles by Arthur Ashkin and others. 1986 abstract: single-beam trapping in water
A physicist who researched nonlinear optics and optical trapping at Bell Laboratories.[ref]
In Memoriam: Arthur Ashkin, 1922–2020 by Optical Society. Independent professional identity
Portrait of Arthur Ashkin
. Bengt Nyman; existing crop, resizing, levels, color and sharpening by WikiPedant. Creative Commons Attribution 2.0 Generic., via Wikimedia Commons. Source.
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