Department of Physics
Laser induced surface stress on water droplets
Laser induced stress on spherical water droplets is studied. At mechanical equilibrium, the body stress vanishes therefore we consider only the surface stress. The surface stress on sub-wavelength droplets is slightly weaker along the light propagation direction. For larger droplets, due to their light focusing effect, the forward stress is significantly enhanced. For a particle roughly 3 micron in radius, when it is excited at whispering gallery mode with Q ∼ 104 by a 1 Watt Gaussian beam, the stress can be enhanced by two orders of magnitude, and can be comparable with the Laplace pressure.
Source Publication Title
Optical Society of America
The supports from HK RGC through grants HKBU 604011, HKBU 603312, and HKBU 209913 are gratefully acknowledged. NW and ZL were also supported by the China 973 Project (Nos. 2011CB922004 and 2013CB632701) and China National Natural Science Foundation (No. 11174059). Computational resources were supported by the Information Technology Office of HKBU.
Link to Publisher's Edition
Wang, Neng, Zhifang Lin, and Jack Ng. "Laser induced surface stress on water droplets." Optics Express 22.20 (2014): 23770-23775.