dr Sławomir Drobczyński, PWr

Optical tweezers. The Nobel Prize in Physics 2018

The theory of light pressure was introduced by James Clerk Maxwell in 1873. Fact that light might exert optical force was confirmed experimentally in 1900 by the Russian physicist Piotr Lebedev. A significant breakthrough in the study of optical forces occurred only after the appearance of lasers. A pioneer of experiments with a highly focused laser beam acting on dielectric microobjects was Arthur Ashkin. In 1986, he published his work , in which he described the first successful attempt of optical trapping using a single laser beam. Optical trapping results from the small forces associated with the electric field gradient acting on the dielectric microparticles located in the focused laser beam. Laser beams with powers of hundreds of milliwatts are capable of exerting forces of piconewton orders. Optical trapping technique applicable in many fields of science. Within a few years from the publication of the work by Ashkin, many laboratories around the world have begun many interesting studies. Optical tweezers can be used to manipulate non-living and living matter. It soon turned out that the optical trapping technology allows carrying out previously unattainable tests on the microscale. The possibility of a non-invasive and sterile hold of micro-objects, e.g. cells or biomolecules, has found particular application in biology and medicine.