LASER TWEEZERS AND RAMAN SPECTROSCOPY SYSTEMS AND METHODS FOR STUDYING MICROSCOPIC PARTICLES

摘要

Methods and systems for studying microscopic particles are provided. An optical trap for a selected microscopic particle is formed with a laser beam at a first power level. The laser beam can have a variable power level associated therewith. The variable power level can be increased to a second power level. The second power level provided sufficient excitation energy to the selected microscopic particle to produce Ramanscattering signals. A Raman spectrum is detected from the Raman scattering signals produced by the laser beam at the second power level. This incident laser beam and/or the Raman scattering signals may be focused by confocal apertures. Non-transparent or metallic particles may be trapped by focusing the laser beam near the distal side of the selected particle to the laser source. In this case the trapping laser beam may have the same power level as the exciting laser beam or a lower power level than the exciting laser beam.