Moving matter with light is a phenomenon generally only seen in astronomy, where light intensities and distances are very large. However, lasers provide enough intensity and coherence to manipulate small masses here on earth. In the past 25 years, scientists have developed laser devices which can accelerate, decelerate, guide and trap particles with sizes from tens of nanometers to tens of micrometers. These devices have been used to manipulate small dielectric spheres, atoms, large molecules, viruses, single cells, and even organelles within cells. In this talk, I will present the fundamentals of optical trapping and some recent applications to single particle sampling, with emphasis on those used in Raman spectroscopy.
References:
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