The Sharpest Focus
Improve your focus. Radially polarized light maintains high symmetry when focused (lef), unlike linearly polarized light (right). Researchers exploited this advantage, and focused light to the smallest spot ever. Image Credit: A. Meixner/Univ. of Seigen
A team of researchers has announced a new technique allows light to be focused to a smaller spot than ever before. They focused laser light with an unusual polarization down to a spot about 0.06 square micrometers in area, almost half again as small as the previous record. The tightly focused light produces an intense electromagnetic field that could be used as a probe or to manipulate atoms or other tiny objects. Researchers might also use the technique in any device that requires highly focused light, such as in microscopes or machines that etch microscale devices.