The Generation and Assembly of Laser-Induced Microbubbles

Microbubbles have broad applications for optofluidic devices, optical manipulation, and sensing. Here we report a series of experimental observations, demonstrating the controllable generation and assembly of microbubbles by using an optical fiber-coupled laser. The microbubbles can be photothermally generated with high efficiency in deionized water, without adding light-absorbing nanomaterials. The temporal evolution and assembled pattern, quantified by diameter, number and density of the microbubbles, can be flexibly controlled by the surface area of liquid, the insertion depth of fiber, and the laser power for heating. Good repeatability is confirmed for the microbubble generation. This kind of microbubble may have the potential for sensing, microstructure formation, etc.