Research Experiences for Undergraduates (REU) fellowships are awarded to undergraduates from four-year colleges and universities for participation in a ten-week summer program. Students enjoy innovative research, professional development, and social activities all in the heart of New York City.
A computer-generated hologram projects a beam of light that focuses to interlocking inclined rings, a simple knot known as a Hopf link. Each ring acts as an optical trap that can gather and hold micrometer-scale objects. The same hologram also imposes phase gradients around the Hopf link, thereby creating a knot in the total optical force field.