Optical Trapping of Metallic Nanoparticles using Microbubbles

In our previous work, the induced force on a microbubble due to a focused laser beam has been studied by deriving a general optical force model. It has also been shown that the microbubble, without and with agglomerated metallic nanoparticles, can be steered using a low power laser beam. An equivalent optical force for a microbubble surrounded by nanoparticles has been also calculated and presented in our previous work. While only optical forces acting on the microbubbles and nanoparticles have so far been considered, in this work the effect of surface tension force is considered and calculated using the temperature gradient generated by the focused trapping laser beam and compared with optical forces. Experiments are performed to observe the behavior of the microbubbles in the vicinity of a focused laser beam for five different wavelengths.