These are a few short clips illustrating the phenomenon of optical trapping. Essentially, a felt tip marker is briefly burned just above the focal point of a ~250mW 650nm laser, releasing an extremely small particle. This is not the intersection between the laser and some smoke; it's an actual particle embedded in the laser beam.
Because radiation can exert pressure on objects, there is a set of force vectors always keeping the particle just above the waist of the beam. This phenomenon illustrates how light can behave as particles (photons) because the photons have momentum and are therefore able to impart forces onto objects. It is even possible to move the laser around gently and the particle will follow along.
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